hi,
I have experienced a problem with a simple material
https://answers.unrealengine.com/questions/141763/bug-in-material-with-tiling-texture-in-android-d.html#answer-147446
In some devices (Samsung Galaxy S1) instead of tiling with “wrap” it seems it tiles with “clamp”. I found a workaround which consists in using a different texture (POT2 and Square, maybe POT2 is the real issue idk).
I think is worth mentioning here both for visibility (further investigation is needed) and the workaround might be useful for someone else.