Snapr.pw is an alternative to Gyazo, don't know what Gyazo is? It is a tool that let you share your (a part) of your screen really simple. It captures (a part of it) and it automaticly uploads it to the site. And you will get the link so you can share it with your friends.
3 reasons you gonna like this more than Gyazo:
Currently hosting 3973 images with a total size of 653 MB.
Stop asking me for the source of the application, search for it on google. It is publicly available.