Here is the story. I have two kids (5-7 years), they have their Android tablets... and I have the credit card. I have created two google accounts, each for one tablet. I want to buy apps for them, but I don't want to enter any details of my credit card to their google accounts, because the theory is that they will be using these accounts in future to communicate, browse etc. I don't want them charging my card without my knowledge.
A while ago, when buying something in the google play store, I was able to select between one of the tablet accounts and my own account. I then had to enter the password to my own account and was able to install the given app. Now this seems no longer to be possible.
I am lost. I am a 40+ year old Un*x user and I am confused and frustrated by Android. Is there a way of buying apps for my kids that is safe?