Since this is an Android forum, and we don't know his likes and what he already has ...
A cellphone?
A tablet?
In either case, stay away from the cheap, no-name devices. If you have a problem, no one else has one, so no one will be able to give you much help. Look for one that's just been replaced by a newer model - you'll save money and buy a known item.
But, as I said, we have nothing to go on, so any suggestion may be far field. Maybe ask a few of his friends, in private, and ask them not to spill the beans, if he's recently mentioned anything he really wants. (My grandkids [the younger one is 11] are usually thrilled with computer games. We just have to figure out which games they want each year.)