You can publish your Android APP via Google Play store, if you provide a description HowTo replace the Qt libraries (.so) which means you must provide your APK file together with a recipe HowTo do this.

No one would do this for a mobile APP, but these are the rules which make sense if Qt is used for Device Creation in embedded market. Your own APP can be sold commercial, but the user must be able to replace the Qt Libraries. Here’s a great german blog discussing LGPL 3 and GPL 3 for commercial projects: Using Qt Essentials and Add-Ons -> LGPL 3 The answer isn’t easy and I’m not a lawyer ! What does this mean for your mobile APPs ? Can you use the Open Source version of Qt ? There’s a Blog describing all these changes in detail: Later this year the QML Compiler will also be included into Open Source license.

Not only LGPL 3 is new for Qt 5.7 – also some Tools (Charts, Data Visualization, …) only available for commercial license before will become Open Source, but as GPL 3. qt.ntrols are only a Tech Preview in 5.6 and will be part of Qt 5.7. I’m starting with Qt 5.6 to test the new UI Controls from qt.ntrols. Up to Qt 5.6 the LGPL 2.1 was used, from Qt 5.7+ the LGPL 3 will be used. It’s great to rely on an Open Source framework – you always can take a look how things are implemented. Since 1998 the KDE Free Qt Foundation guarantees Qt availability for Open Source Development. Qt exists since more then 20 years ! Take a look at the history: Open Source

Qt commercial license file