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I wish Google had allowed the master account to control the installed apps on other accounts, rather than the "you can reinstall any app almost instantly - but have to buy paid apps again." model. It's nice that apps you reinstall on a second account install in seconds with no download, but the fact you must repurchase apps for the same device (as far as I can see) just to use it on another account is horrible and money grabbing of them! I've yet to try signing up with the same Gmail account - maybe that works?!
It just may.
I bought Minecraft for my son and on my wife's iPhone I just logged her out, logged in under my account, free downloaded Minecraft and it worked while she can still use apps downloaded under her account.