The iWorks suite is free and supposedly some of the best productivity software on iOS. You can get the Microsoft office suite as well, but I think there's some in app payment going on there. Whatever you were using in android or windows phone is almost certainly there too.
There's loads of games in the App Store. I'm not sure what is exclusive to iOS though. Infinity blade is fun, and you can get cool stuff like the walking dead and the wolf among us by telltale games. I've never been much for the simpler games like angry birds and candy crush and the like, but all that stuff is there too. I prefer the graphically impressive games myself.
For email I use the default app in my phone and the gmail app on my ipad. If you use gmail you'll have to use the gmail app to get push emails, so that's a consideration.
As for the rest, there's not much to know. For all the bickering we do, iOS works much the same as android. There are some restrictions of course. You'll need to get used to iTunes to easily transfer things to your device, but learning how to use smart playlists and convert video files to formats that iTunes accepts makes that easier than people would have you believe. There are ways to do it without iTunes as well, but I never got into that.