As the image above shows, you can either:
a) Post immediately
b) Only shorten the URL to use elsewhere (other social media networks, blogs, etc.)
c) Schedule your post for later
Below you can see the uses of Su.pr, which makes it a productive and MUST try tool.
1. Get Short URLs for your Blog Posts
Yes, Su.pr provides short URLs for all your blog posts. Within few seconds they’ll generate a cool URL for your posts. You can then use this short link for sharing on Social Networks or any other resource. For HBB, we made our own short URL – HBB.ME. For example,
Main URL : http://hellboundbloggers.com/2011/09/25/things-bloggers-can-learn-from-action-movies/
Su.pr Short URL : http://su.pr/AD81v3
HBB Short URL : http://hbb.me/133
2. Schedule for later
Suppose if you want to promote your posts (old or new ones), you can schedule them for a desired time period using Su.pr. You can specify the date and time to be precise. They will be automatically posted on the accounts (Twitter and Facebook mostly) associated with Su.pr on that time.
3. Tweet from multiple accounts
You can add multiple Twitter accounts on Su.pr and with just a click you can tweet in all those accounts without pain. You just need to authorize Su.pr to use your Twitter accounts.
4. Update Facebook profile and page
You can also update your status or your Facebook page using Su.pr. Just connect your profile with Su.pr, it will detect the pages you admin and you can move with that.
You just need to authorize Su.pr to use your Facebook profile and respective pages you admin.
5. Get suggested posting time
Su.pr tracks your traffic and suggests when you can post to get maximum traffic. This includes the accounts you connected with, like Twitter, Facebook and StumbleUpon. 
6. Su.pr Short URLs on your own domain
This feature is currently in Beta. It is available only for servers running on PHP 5. If you use WordPress, setting up short URLs on your own domain just got easier. You can check this for more info.




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