Just short links that are too long for Twitter, which contain an affilate ID, or simply out of convenience. With a nice and intuitive design, it is easier than never before to make your URLs a bit shorter.
These URL providers are currently supported:
• short1.link (Old short.simolation.de links still work)
More will follow soon :)
Also, you have all your shortened URLs in view with your personal history.
In the statistics for goo.gl and short1.link you can even see how many calls your URL has and much more.
More information on http://short1.link/