Q: Ask to buy

Approve or decline request from iphone , ipad , ipod touch and MAC

Request and make purchases with Ask to Buy - Apple Support

I am setting up an ipod for my nephew and the having same issue, parents are not using any apple iphone , ipad , ipod or mac. Did you have any luck solving it?

For 'ask to buy' and authorising purchases it's still the same - from the link in the previous reply :

The organizer can review the item and make the purchase or decline the request right from their own iPhone, iPad, or iPod touch with iOS 8 and later or Mac with OS X Yosemite and later

But they don't have any iOS devices of their own only the kids iPod. They are using android. Is there no other way?

Not with 'ask to buy'. The parents could not tell the child the account's password so that he has to go to them for one of them to type in the password to allow the purchase (or not type in the password to deny it)