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How much cost Qt for Indie developers ?

  • Qt would not stand where it stays today, if they would not have so many developers. And most contributions are not made from hobbyists, they are made by commercial programmers. If I
    sell successfully a commercial application, I would be happy to buy a licence, because I make sure that my foundation will not break away. And that is quite a crucial benefit.... Just my two cents.



  • It is a pity Digia doesn't distinguish between rich corporations and poor independent developers. And I keep hearing stuff like "It is not expensive" mostly by people whose sight goes about as far as their noses, in complete ignorance of the fact many people in the world still have to survive and provide for families with monthly pay that is lower than a day's pay for others. That is right, the average monthly pay where I come from is less than a day's pay of an average C++ developer in western nations. But hey, since when do rich people give a damn about the poor?

    Paid support I can live without. I never ever resorted to customer support with the exception of returning faulty hardware. It is a very ugly thing that Digia don't take into consideration the financial capabilities of developers, especially after they got Qt literally for peanuts. Maybe I'd understand if they (over)paid as much as Nokia, but getting it so cheap and milking it so hard draws a picture in a pretty greedy tone.

    And while some people say "what do you care, just use LGPL and link dynamically" but many others seem to think that if you develop closed source applications you pretty much have to go commercial, the whole subject is very vague, everyone gives a vague answer, so the poor independent developer is faced with a dilemma - just as he can't afford to buy a commercial license he can't also afford to get sued.

    So how does one start developing and selling his software so he can reach the point of being able to afford either the ridiculously high priced commercial license or the ridiculously high priced legal council?

    And excuse me but those prices are not just high relative to the standards of people who live east of Germany, they are also quite high compared to other similar products:

    C++ Bulder XE3 Starter - 236 euro
    C++ Bulder XE3 Ultimate - 2676 euro
    C++ Bulder XE3 Pro - 891 euro
    C++ Bulder XE3 Enterprise - 1784 euro
    Juce (single product) - 399 pounds
    Juce (unlimited) - 699 pounds
    Visual Studio 2012 Pro - 600 euro
    Marmalade SDK Indie - 499$
    Marmalade SDK Plus - 1499$
    MoSync Basic Pro - 199 euro
    MoSync Gold Pro - 2999 euro
    MoSync (without support) - FREE

    And all those include multiple platform support, which for Qt comes at in excess of 6000 euro. And this only for the currently supported platforms, there is still the possibility to jack the price even further once iOS and Android are supported.

    With all the ambiguity the only good LGPL serves is to attract more potential commercial customers, not to mention it can very well entrap naive people into legal troubles. Surely it must be safe to develop open source applications, but the question is who will pay for an open source application? Maybe a few people will pay for support, but that implies you already have a business with support staff, which is hardly the case of start-up indie developers.

    A much better option for indie developers would be to get commercial license at the cost of 10% of your application sales. Whether you are entitled to support and how much would depend on the scale of your operation. When or if you get big enough - switch to the current fixed price licensing scheme. This approach would make it much easier for indie developers, but it will also increase Digia's profits, provided of course it is willing to collect amounts below 4 digit, and most importantly - it will provide the possibility to start up and grow big enough to be able to afford the full blown license.

    Otherwise, it is just discriminatory towards people whose only fault is no one asked them about the geographic coordinates to be born at.

  • [quote author="mhcrnl" date="1363537675"]Good point
    bq. Let’s be happy that there are that much options and everyone can choose what fits ones [/quote]

  • Moderators

    utcenter: Have you bothered to ask about prices yourself or is this rant based entirely on hearsay?

    At least please do not put the blame for the complexity of laws surrounding licenses at our door. Every country thinks it is a good idea to come up with slightly different rules, there is nothing we can do about that. What we can do is pick a widely used (and hopefully understood) license like GPL or LGPL. Guess what: Those are the licenses Qt is under for a long time now.

    We do have lots of idealists here at Digia that work on Qt because they want to have a good free (as in freedom) library available for everybody. I am one of them and find your claim that the LGPL license is only there to "entrap naive people into legal troubles" or to "attract commercial customers" insulting. A lot of work was put into those licenses by the FSF to make them as clear as possible. A lot of developers have written code under those licenses, because they do like the ideas encoded in them. I feel that your claim belittles the hard work of all those people in addition to anybody contributing to Qt -- inside and outside of Digia -- because it is free software.

    Before you ask: I am not only idealistic but also hungry. I am more than fine with the commercial license option;)

  • I've got enough sources with sufficient consistency across the board to justify assuming their legitimacy. Or maybe you imply I am going to get a different answer? Anyway, I am not in the habit of asking the price of things I can't afford - it is pointless. And furthermore - every similar company has been "kind" enough to provide public pricing, that's how consumerism works - you have a product, you put it on the shelf and you put a price tag on it. What's the deal with having to ask? To be honest I am more curious about the reason why than the actual price.

    Whether you feel insulted depends more on you than on my intent. I've seen my fair share of people who look down on the less fortunate, like if they cannot afford to fund intellectual activities they should quit and instead get into something more fitting their stature - like digging in the garbage cans for food scraps and stuff like that. But unlike you I won't get insulted just because you hold the underprivileged in contempt.

    A multi platform commercial Qt license is a month's pay... if you've been lucky enough to be born in the right place. Sadly this applies to a very small portion of the world population, as a sentient adult you should be aware of that little fact. Glad to hear you are in good financial health, and I wish you live long enough to experience the effects of the poverty that's creeping from east to west. Perhaps then you will understand what you fail to understand today. It wasn't always like that here you know, but one morning you wake up and you find your savings have lost three zeroes, cost of living higher than in rich countries, unemployment skyrocketing and pay - conflicting you whether you should laugh or cry.

    If the intent of the company you represent is as noble as you appear to imply, it should really do something more to help people start up. I am not talking about charity, I am talking about a chance to start up and be able to afford your product through your product.

    Also, correct me if I am wrong, but Qt under LGPL is not a product of Digia - it was done by Nokia. At this point it is unclear if there would be a LGPL option if it was up to Digia. And LGPL is still here because Digia can't remove that option, even if they wanted to, right? So if I were you I wouldn't talk about noble aspirations before there are any expressed in action.

    Last but not least - like 99.99% of the people I've interacted with, you seem to be unclear on the concept of Idealism and Realism as defined by their pioneers - Aristotle and Socrates, and instead harbor the "popular" concept which is pretty much the full opposite of what was originally intended. If you were Idealistic in the true meaning of it - you'd not conform to the static way things are and accepting it for granted and would instead be willing to explore a more flexible solution that better fits the varying scenarios.

  • Moderators

    I said that it is insulting to call LGPL/GPL traps for naive people meant to lure them into legal trouble. There was lots of thought, time and energy put into those licenses to make them as clear as possible and to minimize legal risks for everybody. All that is completely independent of Qt.

    A company is a legal construct with the aim of earning money, nothing more, nothing less. I did not imply that any company is more or less noble than any other company. I do not see where you got that impression.

    Since I do not know much about Qt pricing I can not comment on that topic.

    It is sad that you have fallen on hard times. But how would a commercial license for Qt help you in your situation? You are free to legally use Qt already.

  • Don't worry about me, I am describing the situation around me, I am fortunate enough to be a little better than my surroundings, even if still pretty bad compared to your standards. It is not an individual misfortune, this is the reality of most of the people round this part of the globe.

    bq. You are free to legally use Qt already.

    But am I? What's to guarantee that, besides wishful thinking? Also use as in? Tinker with? Learn? Make money on? After spending a lot of time investigating the matter I honestly don't feel 100% safe doing the latter.

    I admit, I am yet to launch a mass application, I am pretty new to Qt and so far have only done a few highly custom applications for individual clients. Mostly under the table, so no worries there. I would like to launch mass applications but I don't have the resources to afford neither the commercial license to feel safe, nor the legal representation to feel safe with LGPL.

    I am also yet to stumble upon a success story of a sole independent developer who makes a living on Qt under LGPL. The few people I know working with Qt professionally are employed by fairly big companies abroad, Qt is rather unpopular on the local job market, which is odd considering I live in a 2+ million people city.

    I'd be willing to part with 10% of what my products would generate, whether that is 1000 or 1000000, but taking a few thousand euro out of my pocked in advance - I honestly don't feel comfortable with, considering the grim and worsening financial situation. It is not that much a matter of not having the money, it is a matter of not being able to afford it, there is a subtle difference.

  • We're a company that sells our devices with the related software world wide. And we have no issue at all using LGPL Qt. There are many other examples. Qt even has a special exception that explicitly allows you to use things like templates, structures and constants defined in the Qt headers without that leading to you having to open up your sources.

    Before my current job, I also have done work as an independent contractor for several clients. There too, I have used Qt under LGPL successfully. So there you have it: your success story.

    It is nobodies fault that you "don't feel comfortable" with using LGPL. I think it is the most liberal license you can reasonably expect for something like Qt. Seeing that Digia employs over 80 developers (not counting support) to work on Qt, I think the prices are reasonable. We'd all like to see them lower, but it is the way it is.

  • [quote author="Andre" date="1363766578"]
    It is nobodies fault that you "don't feel comfortable" with using LGPL. [/quote]

    You make it sound as it if is based my choice, but in reality it is based on the information available, to a large extend the information made available by Digia. And yes, I keep in mind the fact that Digia representatives may be inclined to bias toward the need of commercial license.

    Thanks for sharing that information.

  • Come on, the license text is right there to read. Futhermore, LGPL is is all over the net. What more information do you need exactly?

  • Moderators

    I would be able to follow your argument if Qt was under some obscure license (anyone remembers QPL?), but GPL/LGPL are two of the most widely used and discussed open source licenses available on the planet!

    When you are going to build a business, you will need to understand the legal implications of your actions. Software licenses are one part of those legal implications you need to understand, it does matter little whether those licenses are open source ones or proprietary.

  • IIRC there is still some ambiguity in LGPL concerning the interpretation of some legal definitions, and then there are the other licenses of other Qt components and IIRC must also be taken in consideration.

    The legal and IP systems are a mess of nonsense and I really don't think I can force myself to "understand" such, that is why I think it is preferable if there was a more affordable commercial licensing option, so I can think about application development instead of legal nonsense. If Digia is that much concerned with the collective well-being, it should include licensing options suited for small and independent developers, so we can develop in peace. After all, a modest fee is better than no fee, isn't it? Or perhaps it is below the dignity of your company to bother collecting bellow a certain amount?

    You know that some time ago an Australian person actually patented the wheel, hidden behind a more obscure technical definition, just for the sake of proving how ridiculous the whole subject is.

    Self-employment has already forced me to become part-time-accountant, and that is one nonsense too many on my head already. So pardon my lack of enthusiasm when it comes to legal issues as well.

  • Patent law is something separate from software licenses. While that too is an interesting discussion, let's not confuse the issue at hand even more.

    I don't think that it has anything to do with being "below the dignity" of Digia (and before them, Nokia and Trolltech). I guess (not know) that it is a matter of company economics: there are costs involved with dealing with contracts and customers, and even more so with contracts for sales-based licensing fees. I think Digia simply figures that the costs involved don't weigh up to the income and the risks involved. After all: if you say that you want to pay a fee per shipped product, that also means that there would need to be communication about that, time and time again. It needs administrating. It needs checking. It can only be done after the fact, and that means Digia would have to go after companies and "Indies" to collect the actual fees. If that is possible at all (businesses come and go, people may be hard to locate, etc).

    I have also seen the commercial license terms. They are not a pretty read either to be honest. I think that with any contract, especially for companies operating globally, there will be difficulties interpreting the exact terms that apply, and how definitions in there match the ones within the legal jurisdiction you're in.

    Do you have any evidence of problems caused by applying an LGPL license? Have you ever heard of Digia or Nokia going after developers using it?

  • So somehow Digia's costs are a lot higher than those of other companies who do offer more affordable licensing? If other companies find it economically viable to collect 300-600 Euro, why should it not be possible for Digia?

    And no, in my last post I wasn't talking about a percent of app sales, but a more affordable indie license cost, something more reasonable like 600 Euro. I'd be happy to get a commercial Qt license for 600 Euro, which is in check with what other frameworks cost indie developers. As the size of my operation grows there won't be a problem switching to the 6000 Euro version.

    No, I haven't stumbled upon stories of Digia going after anyone, don't know if there are such cases, but if there aren't that might be because others exercise the same caution as I do. Better safe than sorry right?

  • Well, you just said:
    [quote]I’d be willing to part with 10% of what my products would generate, whether that is 1000 or 1000000, but taking a few thousand euro out of my pocked in advance – I honestly don’t feel comfortable with, considering the grim and worsening financial situation. It is not that much a matter of not having the money, it is a matter of not being able to afford it, there is a subtle difference.[/quote]

    I took that as a request for taking a licensing fee based on sales.

    Now, it seems that all you really want is a 90% discount. Based on what criteria exactly? Why would anyone buy a full license if they can get the same for only 10% of the price?

    It really seems to me, that you have plenty of options already available to you. You can use LGPL, you can use GPL (yes, you can make money with GPL-ed software) or you use a commercial Qt license. Or, you take a cheaper, competing framework.

    Anyway, I am not in sales, and hope I will never be. I don't design pricing plans for any company.

  • bq. and no, in my last post I wasn’t talking about a percent of app sales

    I'll be happy with either of the options. I proposed the 10% scheme because it will be better for indie developers as well as for Digia. But an affordable indie license is just a good.

    No, I don't want discount, I want a license option that is reasonably priced according to individual independent start-up developers. I am even willing to leave out modules I don't need, if you really feel like а reasonably priced indie license will rob the revenue. Plus as I mentioned previously - I could also go without actual customer support. But still, 600 euro is better than 0 euro and it paves the way to 6000 euro.

  • OK I can't say I'm a huge fan of the current licensing arrangement.

    Having tried to get my head round it for a while I have come to the following
    License is actually a pretty good deal for many independent developers. More precisely,
    the developers that don't need to modify QT source and don't need to statically link don't
    seem to need to pay a thing (which is why I say its a good deal).

    Unfortunately if you do need to do these things then its very painful indeed.

    Now why all the confusion about the license ? I think its probable that Digia want to sell as many
    Licenses as possible so don't mind having a little uncertainty in the minds of the richer independent
    developers (ones can afford the price but might skip the payment if they thought they didn't need
    to pay) What I'm saying is there are a certain number of cashed up developers that roll their eyes
    at all the legal mumbo jumbo and reach for their credit card.

  • What confusion?

    You require a commercial license for static linking and closed-source modifications of Qt; if you get along with dynamic linking and the fact, that you will have to provide the sources of modifications of Qt (not your application) if you publicly publish your application you will get Qt for free under the terms of the LGPL or the GPL.

    If you are interest in the prices of Qt feel free to ask Digia.

  • Thanks Lukas you just made something more clear to me: So I can use QT for free
    for a commercial closed source application provided I 1) use dynamic linking 2)Publish source code of modifications to QT. Cool, since I'm happy to publish my mods to QT (if I make any)
    and for most application style applications dynamic linking is preferred as a matter of good software engineering. So as far as I can see the only real prohibition the on use of the free
    license is using QT to make binary libs, since these must to be statically linked.

    I still do like my confusion theory its got a nice whiff of conspiracy about it.

  • Yes ^1^.

    No, it does not have a nice whiff of conspiracy, it just disparages the people working on Qt giving you the right to use their work beeing created investing a large amount of their resources for free, enabling you making money.

    ^1^ IANAL.

  • Lukas take a chill pill. I think its pretty clear that my remark was meant in jest.
    As for making money, pretty well everything I do is in the public domain and I don't make money out of it.

  • No reason to feel offended.

    You have your theory and you like it; I don't, for the reasons given.

  • But what about the future?
    I work in a small software company. We can't afford ourselves to port our applications to a new framework each year. The question is as follows: is it possible that Digia will close the sources of the next version of Qt and drops the support of older versions while one will have to pay 60 000 euros for the only available commercial version? Something other like that: will the whole Qt technology be dropped from development?

    It will be so nice to hear your opinion including the opinions of professionals that keep their nose close to wind with Qt technology and Digia's licensing.

  • [quote author="zzz9_z" date="1368448854"]... is it possible that Digia will close the sources of the next version of Qt and drops the support of older versions while one will have to pay 60 000 euros for the only available commercial version? ... [/quote]
    Thats sounds like a some scary story...
    I hope its not happend. Anyway if Digia decide close the Qt sources, Qt will continue live in GPL. Of course Digias version will evolves faster but Qt as we know today never die.

  • Moderators

    zzz9_z, qxoz: That case is actually covered by the "free Qt foundation":

    Basically if Digia stops releasing GPL/LGPL Qt versions than the code becomes available under a BSD license for everybody to use as they see fit (incl. commercial use and whatnot).

    I think the availability of Qt to you as a business is way more certain than any other toolkit out there.

  • Tobias Hunger, that sounds good, still developers have a guarantee that they can still use Qt in their already written applications.

    Regarding the previous messages about the price of the framework: you pointed right about passion and hunger.

    Regularly there is no need to make his own version of Qt for an indie (there is sometimes workaround for some cases) and large companies can afford this price themselves (to make the development like conveyer, for example adding an ability to set custom QTabBar for QMdiArea out of the box). I see some small commercial projects (like GameCore) use Qt for their tools, I don't think they have a commercial license for developing a set of windows with buttons.

    I don't know where this license paranoia comes from. I have defeated mine one after you clarified some questions. Maybe Qt Project must have a special "License Paranoia FAQ" covering all of its aspects, seriously!

    I still have some questions about older versions of Qt like 4.7. Are they still supported: bug fixes, updates or one should port to the newer version to see them in Qt? I mean, what is the model of Qt development: 1. 'dropping' the older version and switching to a new one or 2. developing the new Qt version while making bug fixes and small updates to the old one? Sorry for offtopic but I think it is indirectly relates to the topic (buying the newer Qt version).

  • Could you (or someone else) please elaborate on the fact that you can use the LGPL license to develop commercial Qt driven applications?
    Where does the limit go? If you include libraries as runtime libs, if you use static linking? How does it work in practice?

    I've tried to read the LGPL licence but the definitions are vague at best...

    [quote author="Andre" date="1316158186"]When the licences were still sold by Nokia, I believe that they cost something like EUR 1400 per developer for a single platform licence. You could also buy a 2 or 3 platform licence at a few hundred per additional platform. No idea if Digia is using a very different price model, but I doubt it.

    If you need more exact data, you have to ask Digia, of course.

    Note that you may also considder using the LGPL version of the toolkit. That would be a much cheaper option for an "indie", I think. The limitations are not such that it is impossible to develop commercial software that way. [/quote]

  • But still. The current pricing is not friendly to individual developers who actually wishes to get the benefits of a commercial license. For most people it's a huge amount of money, and the prices are in my eyes targeted at corporations and not single developers.

    Is it not possible that by offering a more fine grained price structure, more developers might actually be able to/want to pay for a license?

  • What kind of benefits you talking about?

  • qxoz: Direct support, peace of mind, the ability to ["legally"] statically compile if needed. Complete freedom. Stuff like that.

  • Well, I think most independent developers are satisfied with the current state of affairs. Even if reduce the price of the commercial version, do you think strongly increase the number wanting to buy?
    Static build and direct support are not critical for indie developers, peace of mind - most people even don't know how is it :) .
    Maybe good reason for buying would be a tools like Charts, but i dont know.

  • I think that most people are happy with the terms too. It's up to the individual to judge whether one actually gains from the stated benefits.

    Personally, I'm finding myself in situations where I wish I had more veto power, so to speak, in order to push development for certain features. My development platform is Mac OS, and there's still missing critical features in 5.1 that prevents my current product getting in a finished state. With a commercial license in hand, I would feel that I had the right to raise my voice higher. As it is now, the answer I'm getting is more or less "we happily accept patches".

    Different strokes for different people. Yes, I believe a reduced price would increase sales significantly.

  • I still feel confused.
    Can someone explain how I would go about developing an application that I could sell commercially, built with Qt Components, like:

    Use the Qt Creator IDE with the Widgets and bells, Create a GUI (possibly with QML) and the C++ code behind (using Qt libraries), compile it to executable code and possibly creating an installer, then sell it as a commercial app, using the LGPL licensed version of the Qt tool-set?

    Ces't possible?

  • cseder: As long as you don't modify Qt and don't statically compile, you're good to go.

  • Ok! Thanks. Finally a clear cut answer.
    I can live with those limitations.

    Then I don't have to hunt for and learn another GUI framework after all... ;-)

  • Your freedom even goes a bit further than that, but let's not cloud the issue :)

  • [quote author="Andre" date="1374218615"]Your freedom even goes a bit further than that, but let's not cloud the issue :)[/quote]

    I don't think that would cloud it up in any way, on the contrary I think it would be a nice addition for motivating "indie" developers to use Qt, so, please, make a short list over the additional advantages.

    If you don't feel like posting it to the forum, please pm me with it, as I'm working on a blog entry covering this exact topic.

  • Moderators

    With LGPL:

    • you can distribute your application under any license, including commercial ones
    • you don't have to provide source code of your application to your users

    You have to:

    • provide any large patches to Qt that you are using (for example when you have fixed something in QPoint). Small changes are exempt from this by Qt License extension to LGPL. Also, if you push changes to Qt Project, and they are integrated into Qt, you don't need to provide anything
    • provide license file for Qt
    • allow libraries to be swapped (no static linking)
    • inform your users that Qt is being used (About box, readme, etc.)

    So you can modify Qt itself, but you need to give your users the means to run your application with Qt they build on their own (if they wish to do it).

    With GPL:

    • all your code needs to be GPL'ed, too
    • you need to provide source code to your clients upon request (you don't have to make them publicly available and you don't have to ship them by default. Any recipient can propagate those files, though)

  • While I really like using Qt SDK much more than Visual Studio when I was using it (before C#); Qt Creator is light-years ahead of anything for wxWidgets; I like the idea of running natively to avoid the slow startup and garbage collection vs .NET applications; and I love that it is multi-platform, including phones - it seems overpriced for me. Sure, LGPL is still a good deal, BUT, I am coming across more problems with it than at first seemed apparent when I started:

    1. If you want to, e.g. make VST/RTAS plugins, Qt LGPL is simply a non-starter; unless you are making freeware ones, even if you could solve the technical issues. Users are used to having single DLL's they can re-arrange and copy about; but with Qt5, we are up to 12 DLLs needed to make my application run on a target Windows machine, coming in at 12.5 MB+ (counting one in the "platforms" folder needed to make it run on XP). The same project in Qt4 needed 3 DLL's coming in at a svelte 11.6 MB.

    2. This bloat of DLL's is including things like D3DCompiler, EGL, GLES, and the huge icu*.dll files; most or all of which I'm not even using, but they are required just to run. I assume that statically linked versions are a lot smaller for a total install; since linkers will ordinarily exclude unused functions, etc. This isn't a stopper for me, but developers do like to avoid excess bloat wherever possible. For those who cannot abide the extra bloat, this will be a problem.

    3. If developing for phones, a 36.2 MB program is pretty large; vs. the 12.5 MB my app used to be in Qt4. So, if I want to sell a phone app, must I pay 2995 Eu.; and will my app then be small enough? It's nice that it can cross compile for them, and simulate them, but is it the case that LGPL version is just a non-starter here too?

    For cases #1 & maybe #3, LGPL is a non-starter, and it would be good if they would warn prospective programmers. For case #2, the deliverable install size just bloated considerably, although it is not a stopper. I am not ready to be done with it. Unlike wxWidgets, I can get it to do what I want, in most cases, without undue grief; and they have an excellent IDE (I was really amazed at the ease that it integrated with Git; although I've not needed advanced Git features yet). While LGPL sounds really great, further reflection shows problems with it that are not readily apparent for prospective developers.

    The licensing for Qt is way more expensive than most or all of the competing products. I'd like to see that come down; although M$ doesn't have the LGPL users like Qt. It is quite a boon for FOSS software, of course; but this too cuts into their user base. Will this be a benefit or liability for them in the long run? Time will tell. If you want to develop for both Windows and e.g. Linux, or Windows and say, Andriod phones, when they are supported, am I to understand that one must pay for each, and that isn't included in the 2995 Eu? The cost is staggering to use it in those cases where LGPL doesn't work. I'd suggest that they might have e.g. an enterprise edition and a standard edition, so as to provide something for small developers so they could statically link, and not have to pay what are the highest or among the highest prices in the business.

    Note: edited to reflect the removal of unneeded DLL's.

  • I see people here has discussed pretty much how things really stay and I agree that an indie developer license would be a very nice offer - I would totally buy this license. Still, we're stuck with the licenses that Digia is providing right now and we can't do anything about it.
    I am an indie developer too.. well, not really as much of a developer as I just got out of high school with C++ knowledge and I'm experimenting with Qt. But in my mind I have a lot of projects I'd like to make real, some are very small while others are huge projects; and I'd like to get some money out of them so I could afford better hardware to develop on, and something to live.
    As stated before by others, the only thing that would allow me to make money for free out of Qt-made applications is to use LGPL. But while reading the LGPL license I could not understand all the license statements. It may be because my mother tongue is not English... I don't know...

    So, if that's not too much of asking, could someone please explain the LGPL license in a section-by-section manner, so I can understand all the terms and conditions provided along the license?

    Also, another big issue as I could understand is the deploying size of shared libraries. So, while I still don't get all the terms the LGPL license provides, let's suppose I just decide to use it. Then, when compiling the Qt shared libraries, would I be allowed by LGPL to (and how do I) exclude modules from being compiled in the shared libraries to reduce the final size? e.g. in an application I'm trying to get done right now I don't need to use any other modules than QtGUI, QtCore, QtWidgets and maybe QtNetwork - can I compile just those and exclude all the others?
    And last question, still related to shared libraries; a lot of code on the web (not necessarily Qt) is known to have issues when dynamically linked (probably because of not-that-well-done-code). Does Qt have any of these issues?

    Thanks in advance for anyone willing to answer the amount of questions I made :)

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