Well, while I use the Surface Pro 3, there is a Surface 2 in my house used by a family member and it is one that I have used extensively before I got the SP3.
I used the following to good effect:
ePUB books -> Book Viser (free); Freda (free) - I happen to like Book Viser.
YouTube -> Metro Tube (Free) and You Tube Downloader (though I don't use it too much)
Media Player -> Metro Media Player (Free - pay for MKV)
PDF -> Adobe Touch (free); Drawboard PDF (paid)
News -> Flipboard, News Republic, News Bento
Reddit -> ReddHub
Twitter - Twitter app (though I believe Tweetium (paid) is very good)
Communications -> Skype, Viber (both free)
Misc.: Fresh Paint (though I don't know what to do with it!)
Kindle -> Official Kindle App (though I have not installed it)
Blogging - > WordPress app (though I have not installed it)
All this aside from the MS apps - like Reading List (for saving articles/ pages from websites for reading later - syncs with my other Windows devices including phone), Calculator,
That's about it. Btw, I continue to use these apps on my Surface Pro 3 too!
Sorry, I don't know what PuTTY is.