Cool bike for 12 year old boy

An 11 year old of my acquaintance, great kid, has never had a bike. So his mum has asked me to figure out what bike he should get for his surprise 12th birthday present. Now, I kind of think a 12 year old should be allowed to choose his own bike, but I've accepted the challenge. Only problem is I don't know what 12 year olds are riding these days.

So: His granny lives in the countryside, and I'm going to give him a fixed up GT Performer to use up there so he can rock around on that. But for his home bike (suburbs) and birthday I suppose it should be a mountain bike. But I don't bloody know for sure.

Any insights from the tiny number of forumists who have experience of this kind of stuff is most welcome.

I sorted my little brother out with a Fuji feather when he turned 13 which went down v well. I have another, younger brother too and some of his mates have been on singlespeeds too, but there are pros n cons to that. Personally I don't think kids need the distraction of gears, but also the mountain bike route does often provide a better fit on acct of the smaller wheels (usually)

Whatever it is, make you you give him a ton of cool stickers with it so he can customise it.

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Whatever it is, make you you give him a ton of cool stickers with it so he can customise it.

And a race number. And stunt pegs. And clothes pegs, together with the tops off a few cereal boxes. Get him a spare rear tyre too, because skidding competitions really take their toll.

As well as cool functioning and reliable should be up there , got my first bike and learnt to ride in the last 8 years and not working properly/ not fitting almost put me off riding for life

By a decent mid-range 24 inch bmx, get forks, h/bars and cranks powder-coated.