My 9 year old nephew has a phone, but without cell service (so it's more like a wifi-only tablet) and he doesn't have access to it all day -- I can't remember w

My 9 year old nephew has a phone, but without cell service (so it's more like a wifi-only tablet) and he doesn't have access to it all day -- I can't remember what the schedule is, but he gets like a hour a day of use on school nights and more time on weekends. He mostly plays video games and watches video game walkthroughs on youtube with the phone. For schoolwork he uses the family computer in the livingroom. There's some kind of content filter on it to help keep him from the worst of the internet.