Topic: Do you play 3DS games in 3D or 2D?

I usually play in 2D but occasionally I like to see the effect

3D in games that have depth like Mario Kart 7 or Super Mario 3D Land
2D in well..2D (or 2.5D) games like New Super Mario Bros. 2 and Scribblenauts Unlimited

I didn't really like the 3D at first because it "felt" weird, but after I got used to it I fell in love with it
In 2D games it doesn't really make a difference though..so I just keep it off to conserve battery

I always play in 3D, very rarely will I turn the slider down if I'm playing a game that's meant to be viewed in 3D. Though I will turn it off for VC games and games like Devil Survivor: Overclocked, in Overclocked the 3D effect is almost non existent. Also maybe if I've been playing something like Etrian Odyssey IV for a long time I'll turn it off just because having it off doesn't make TOO much of a difference. But luckily I've never gotten a headache and it doesn't feel like the 3D is straining my eyes so I don't really see the point in having it off. Also playing games like Resident Evil Revelations and Shin Megami Tensei IV just look beautiful in 3D. I also really love the way menus and windows look with the 3D effect on.

Usually 3D though if I'm moving alot or needing to move I will put it into 2D mode.

On the subject of headaches this has happened to me, If i get out of the sweet spot and get that Split screen double image too many times it will trigger a headache. It's because your eyes are suddenly put into shock by the sudden move and they force themselves to try and refocus the image straining them intensely.

While I'm mostly a 3D guy, there are occasional exceptions; increasingly I am open to the idea of a 3DS game where all the hardware is focused on pushing a more beautiful "standard" image.

@PloXyZeRO suggests disabling the 3D effect in side scrollers, especially to conserve battery
and
@thatguyEZ eases off the slider in marathon gaming sessions, to alleviate eye strain

These are good considerations too.

I'm actually starting to use the 3D less and less now-a-days... there simply aren't many games out there at the moment that are using it the 3D effect to good use. Sure it looks really nice and it makes the game stand out and it sucks you into the game a little more, but I'll use it if I really want to use it.

Especially side scrollers, long gaming sessions (as others have already mentioned) or games that simply don't need it (Animal Crossing) then I'll leave it off to conserve battery life. I think we'd all miss the 3D effect if it wasn't there, not because we need it or want it, but just because its there....

Some games look better in 2d and some in 3d. I mostly play in 3d. But if I feel it looks better in 2d I will turn off the 3d.

I only play in 3D. Unless it's Mutant Mudds, which I haven't played in forever. That's the only game I have double vision in. KIU, ACNL, and FEA are all beautiful in 3D.

3D all the way to the point where playing it in 2D seems weird to me. I have grown that used to it.

I would. (Even more so for 60hz instead of 30hz which seems to be a compromise made far too often).

Usually in 2D. Main reason being to conserve battery life.

I always have the 3d on at max. Seems like I'm wasting an important feature of the 3ds if I don't have it on. Also, everything looks flat in 2d.

I always play in 3d.

lol. This is an interesting observation, I'll have to see if this one checks out.

Usually 2D, unless the game benefits from 3D. It's usually not convenient for me to turn on the 3D.

3D.

I always play with 3d turned all the way up! I like to feature to much to not use it and every time I don't the games just feel flat to me. Unlike others, even after a 12 hour session I didn't even have a slight headache, and I don't think I ever will.

Mostly 2D for me. Sometimes I'll turn the 3D on, but usually not longer than 15 minutes. My eyes get iritated after that long. Plus, it's not like much is added for most games by having that depth, at least from my play experience.

Always 2D, for battery life and I don't like having to sit in exactly the right position for the 3D to work. Wouldn't miss the option if it was gone...