How To Change The Default Short Domain In Bitly
The popular link shortening service Bitly can be configured to have other short domains (bit.ly.com and j.mp) instead of the default  bit.ly.
Here is how to change it :
Login to bitly and select “Settings” by clicking on your username.
Next, choose “Advanced”. At this point, if your email address is not verified yet, click on the verify email link and wait for the email....