It seems that using TextInput in some scenarios causes instability on Android (application crashes, crash log attached). This happens often on the "real" application I'm working on - however I was also able to reproduce a crash with a simple test application (attached qml file of a slightly modified hello world).
The crash is a bit difficult to reproduce with the test application, at least manually, but it seems that pushing an item on Stack, focusing/writing on a TextInput, popping with back-button & repeating fast enough will at some point cause it. Unfortunately it happens much more easily on the "real" application.
In addition, I have a feeling that this didn't happen so much before Qt 5.3.2. I don't know it the fact that the stack item in the example being anchored and giving warning about it in the logs has anything to do with the problem