There are thousands of icon sets available for Android, the only trouble is finding the good ones as 90% of them are down right ugly.
As I personally like minimal design, Min may just be my favourite Android icon theme available for the very customisable mobile OS.
The icons don't try to do or be anything fancy. They are a very straight forward solid coloured set of icons that have a very shallow shadow and a slight lighting effect. The icons follow the guidelines of the standard brands so they're easily recognisable - Twitter for example uses the default Twitter bird, same with Instagram and Google+. The icons are trying to be as simple as possible.
The great thing with the solid colour throughout the set means they'll look fantastic with lots of different backgrounds - except very light ones.
The icons are very small but highly detailed and with modern Android devices having exceptionally high pixels per inch, they do look pretty sharp.
Probably the best thing about this icon pack is that it's free so it's worth trying out anyway.