background process in mobile devices. how to?
How to make mobile app so that if killing app the background process be still online.
What is the approach? is there crossplatform way? what to read?
I don't have a direct answer. However, it has to be noted that the mobile devices' OS are ultimately in control of what runs and what doesn't. Depending on the device and the OS, there may not be much you can do to control this. I know from a native code standpoint, on iOS, for instance, there's not really a concept of an ongoing background process; however apps can be woken up periodically to do things.
In short, I don't know there's a cross-platform answer to this. However, if anyone has any ideas, I'm sure they will contribute them.