android app layout not looking properly on some devices

[Purushottam Singh]

Hi i am a beginner in android app development. I have an android app which is works fine on Honeywell D75E(android 4.4), but when i install same app on Zebra TC25(Android Naugat), some of the buttons and items are not visible or visible as stretched/compressed. What can i do to solve it. assuming that the next device has 20% less in size