My favs that I have owned, in order 1 - Vita, 2 - DS Lite, 3 - DS, 4 - GBA. I really didn't like the original GBA at all (because of the screen), and sold it within a month or 2 of launch day purchase. It's just on the my list by default.

The Vita is the best handheld, best phone, and best mobile device I have ever owned.

It is extreamly sad, that the Skype app is loosing support on June 22nd, and I will have to buy a phone for the first time in almost 2 years. Hopefully, the Xperia X will be avialable in time here in the US, or I will be phoneless for a while.

My time with the Vita has produced more gaming than with any other platform I have ever owned, from the NES to the PS4. Between local games, PS Now, and Remote Play, I had sunk 1000's of gaming hours into my Vita. Along with doing business, paying bills, watching TV, etc., etc. etc.

Vita is the best mobile platform ever released, and it is extreamly sad to see it die an early death, while the likes of Android and iOS run wild with such limited scope.

Hopefully, Sony will be able to make a PlayStation Phone based one 7nm tech that runs the PS4 OS, and all PS4/PS4K games. I don't intend to be on Andoid that long.

3ds and gameboy advance

GBA SP!

I'd say 3DS but GBA SP was the best handheld I ever owned.

You know us handheld users are badass when our answers are, "I love X, but enjoy the rest as well".

That's probably why I've always loved the handhelds for gaming. The only disappointment would be Vita, but even then it was still an amazing handheld.

I've used all of Nintendo's handhelds and the PSP- I'll probably get the vita when it's dirt cheap(along with the memory cards)

PSP Go.

I has amazing titles such as FFVII Crisis Core, GoW, MGS PW and all of the PS1 classics, and also you can dock it and play on the big screen using a dualshock 3 controller. (best way to play Crisis Core btw)

...and with the proper mod/emulator it can play NES, SNES, GB, GBA, PS1 games :P

Well if we count BC, then 3DS for sure.

I like my 3DS and GBA together. With those two handhelds, I can play ANY handheld Nintendo game released to date with their combined BC.

I know you said one, but if a little bending of the rules gets me access to them all, what the hell! =P

Not sure if I can pick. I have fond memories with all of the handhelds in the Gameboy line, from Nintendo titles, to RPGs, to other random, but fun games. Still going strong with the 3DS.