Qt 5.6 License for Mobile Platforms

[Ibrahim]

Hi; I developed a mobile application and I want to deploy my application. I am using Qt 5.6 Community Edition (Open Source license) and I compiled dynamic linking, I did not static linking (Bundle Qt libraries in APK). Someone said me: "You are using Community Edition (Open Source license) so you do not deploy your mobile application on Google Play and AppStore.". Can I deploy my mobile application on Google Play and AppStore (and Amazon Appstore, Galaxy Apps, SlideME etc.)? Thanks.

[Mehmet]

As far as I know, yes you should be able to deploy to google playstore, but not to apple appstore, here you need to compile everything statically

[Ibrahim]

Thanks, so I can deploy my application to Google Play, Apple AppStore and others? And if I use QtPurchasing, QtVirtualKeyboard and QtCharts modules in my mobile application so can I deploy my application to Google Play, Apple AppStore and others? (I am using Qt 5.6 Community Edition (Open Source License)).

[jsulm]

As @Mehmet already said: you have to link your app against static Qt build for iOS (Apple does not accept shared libraries). In this case you have to be compliant with GPL license.

[ekkescorner]

Qt Android Apps in Google Play
if your target OS is Android 4 or less you can use Ministro Service to access Qt libraries
Targeting Android 5+ this isn't allowed anymore by Google, so you have to bundle Qt libraries with your APP
To apply to LGPL rules you can bundle the libraries and publish app to Google Play,
but you must provide a way for your users to be able to replace the Qt libraries.
This can be done if you make your APK downloadable for users together with a description HowTo replace libraries. No one will do this for mobile apps, but these are the rules. BTW: your app code itself is secure and must not be open source.

see here, how this can be done:
http://stackoverflow.com/questions/18639508/replace-so-file-in-android-apk
https://gressie.wordpress.com/2012/06/14/how-to-properly-re-assign-a-signature-to-an-android-apk-file/

Qt iOS Apps in App Store
on iOS there's not such an easy way so AFAIK you cannot go this route.
Only if your APP code is Open Source and you provide the link to your Github repo or so you can bundle Qt and publish to Apple's app store.
Normaly your app won't be open source so you have to use a commercial license.

Qt Tools (QtCharts, ...) must be GPL or commercial
If using extra tools like QtCharts you need a commercial license or your APP must be open source under GPL.
on all platforms !
Qt Tools and Applications are commercial only until Qt 5.7 and part of Open Source for Qt 5.8+
http://blog.qt.io/blog/2016/01/13/new-agreement-with-the-kde-free-qt-foundation/

take a look at the new Indiependent dev / startup license for 49$ offer, which will make your decision easier to use commercial license
http://www.qt.io/start-up-plan/

[SamGrant]

So, can someone describe what is actually required to develop and deploy to BOTH Android and iOS?

Let's just assume that I'm OK with ALL my app code being Open Source.

[Ibrahim]

@ekkescorner Qt libraries mean MyAndroidApp.apk -> lib -> armeabi-v7a -> .so files (like libQt5Core.so)? If you mean libraries are this files users open the apk file by winrar or 7zip then they can change libaries. Otherwise I develop small application to change libraries. Am I the condition would have secured the LGPL?

[ekkescorner]

I'm not a lawyer - you should ask one.

for open sourcing your app:
from my understanding providing your project with sources (per ex. at Github) together with a description HowTo install Qt and tools (QtCreator) and HowTo build and deploy the app this is ok for GPL.
then inside your app it must be easy to directly open the link to your open source repo and at first time opening the app the License should be displayed and confirmed by user.

for LGPL without open-sourcing your own app follow the description from the links I provided in my comment above.

again: I'm not a lawyer. it's only my understanding.
I'm using the commercial license for Independent devs / startups, but later this year I'll also publish an Open Source APP - let's see what will happen then ;-)

[SamGrant]

That Startup/Independent license is $49 PER MONTH... not just $49 as you state. Although I appreciate the effort, it's still quite steep for TRUE startups... who may not YET have a reliable revenue stream.

[jsulm]

@SamGrant If your app is open source then there is no need to by a commercial license.