Android because, I don't know, why not, who the hell cares anyway?

Windows Phone.
It's responsive and slick and it stays that way, Android seems to bog down and gets slower the more you install over time, not to mention you have more chance of winning X-Lotto than getting an OS update.

iOS looks and feels absolutely archaic which more-or-less suits it's hardware.

However, that's not to say Windows Phone is perfect though, it's lacking the more obscure apps, like for my banking institute and updates seem to arrive at a snails pace, it's worth it for the slick interface in my opinion.

iOS.

I have to admit, I really look down on Android users; they're typically out of shape, lower social class, lower intelligence, and a foolish type of people. Social parasites if you will. Not the type of people any one of the VPs in my circle would be caught in association with under any circumstances... Except maybe secretaries and cleaning ladies, I can see them with Android phones.

iPhone projects the type of person I am. It's the same reason I drive a BMW, wouldn't be caught in public without a designer suits, unless it's at the spa of course! Having an iPhone is like having an excellent hair cut instead of a cheap buzz cut. It's fine champagne instead of cheap beer. It projects success!

I could go on, but I have a reservation for 1:30 pm at a new premium sushi place that I have been dying to try out. Ta-ta!

For phones? Android For computer? Windows.

I just hope that you are being sarcastic and ironical..

IOS.. but i have all the phones...
I'm really starting to dislike Android with Google forcing more and more "their" apps onto you.. it used to be more open and even worse.. google pressured Samsung to tone down their skin to push google apps

http://recode.net/2014/01/29/after-google-pressure-samsung-will-dial-back-android-tweaks-homegrown-apps/

iOS and android aren't much apart anymore. One may have strength where the other lacks but it's pretty much a tie.
Now you can argue a lot about customization and the "open" feeling of android. But you can also argue that because iOS is somewhat closed in itself it is easier to handle and simply works without the need of knowing anything about the tech behind it.
Thus it comes down to what you like best from that comparison.
You may also prefer android because you don't (want to) support Apple but imo supporting Google isn't any better ;)
If you want to stay away from huge companies who sell stuff for lots of bucks and influence your life in whatever way, you are wrong at both camps.
In the end, nothing is "better". iOS and android are the best and then it's personal taste based on very different factors. Just the same as consoles ;)

They all suck. Windows Phone and iOS are too restricted, Android is not polished enough and seems very inefficient. Symbian is dead and I don't know how the more recent version were, and I have no clue about Blackberry. Meego had potential but it died way too quickly. Sailfish has potential but will probably fail with not enough support.

The title is slightly misleading as typically when people mention OS, they mean PC OS, not mobile OS. In that regard I would very much like to prefer Linux but it's hard when most games are on Windows only.

For me, Android. I prefer Nexus devices, more updates and AOSP Android is way better. Reasons are the better multitasking and more OS resources, closer to a PC. I love the interface to and, as a developer, it has the most mature and feature-rich SDK, so it helps me build more interesting apps.

I had a WP7 too and liked it, but it wasn't not even close to Android's features (WP7 was pretty weak in this points). Can't talk about WP8 because I didn't have one. I have a BlackBerry 10 device and enjoy it too, pretty interesting device.

I tought the same thing when I saw the thread title. OP should change to "prefered mobile OS".