As you all know iOS 5 has complete integration with Twitter, you twitter from anywhere, you can tweet a link, a photo from the reel ... anything. If you enjoy this feature have two options, the first and easiest is to install IOS 5 as we have explained .
The second is to install TwitkaFly, a tweak that does something similar to IOS 4, allows a gesture of Twitter using Activator and also adds a pop-up when you get a mention or a message on twitter.
TwitkaFly costs $ 1.99, good price seeing what it offers, although a little more I advise installing IOS 5 and have this feature natively. If you must stay in IOS 4 + for some reason: this is your tweak.
Need to be jailbroken.