Installing purchased Android apps on multiple devices?

Question

Android

There are a couple of devices under one account (a tablet on Android 5 and a phone on 4.4 are all children). There is an application purchased (tips on how to install without a purchase are not needed now) on a tablet (in particular Minecraft PE).
It seems that I have never experienced problems either with restoring purchases on a new device, or with installing on several devices, but now the problem is that on the phone I am again offered to buy this application, although there is one purchased on the tablet in the same account. The problem is not in re-purchase, I just want to understand - why is it so ...
What could it be connected with?

Answer 1

there are some doubts about the correctness of this statement - read Google's answer here .
And now it is even possible to create family libraries, i.e. use one purchased content (including applications) within several accounts.
But in this particular case, for some reason, it doesn’t work ... There is a suspicion that the problem is in different versions of Google play on devices - on both devices, the firmware is custom, not original.