I thought this is an issue of the latest Build first, but I get the same result with earlier Builds on some devices - on my 10" tablet(Android 7.1.1, display resolution 1920x1200) for example.
The problem is that adjacent Active objects/Backdrops doesn't line up correctly on the device at all positions on the y axis and I can see clearly visible gaps between the top and bottom object edges. It happens after every 1px:
move objects by 1px - no gaps, move 1px again - gaps, move 1px - no gaps ... and so on.
This means I can't place my objects at the desired positions, if I don't want these gaps on some devices? I already created a private bug report just in case, but perhaps this is something that cannot be avoided in the Android runtime - I'm not sure?