QML have currently a bug (current version 5.8 still have) in resize window when android keyboard come up. It happen when virtual keyboard is requested the QML window show a bad flicker by repaint the top control on the center of the screen and back on top again. This look really unprofessional.
Lately, after an Android emulator image update, a strange error regarding OpenGL is coming up using official Android emulator. This error refer to some OpenGL failed operation and, as consequence, doesn't allow the app to run correctly. QML make a large use of OpenGL that's mean each app developed using this technology doesn't work anymore (on the emulator).
QML is a great way to make nice interfaces but, currently, suffer a bit in the initial phase of loading since it could take some time if your QML code is complex or there are many image resources to load. In this case show a splash screen can be a good way to "inform" the user the app is started. More better have an animation will inform also the app is alive and still loading.
Developing an app for Android frequently require to include some additional files containing custom data used by the app itself (in majority of cases sqlite database files). Android provide a standard way by using a special folder called assets where these kind of files need to be stored. Qt Creator provide a instructions to use for copy these files during apk creation.
Make a TextArea control flickable is a very easy task using new version 2 of QtQuick controls. However when Material style was applied it create a very strange problem by inserting a line on bottom side of control that, apparently, can not be removed.