1) The name of the tweak is GravityLockScreen and is developed by Chance Hudson. Basically what this app does is that it adds bounce and gravity into your lockscreen. Flicking the lockscreen upwards will result in the lockscreen bouncing and falling as if it is being influenced by gravity.
2) Fullscreen For Safari
Official app description from Cydia is as follows
Use Safari like never before!
Offers a FullScreen mode. Also makes Safari a real multitouch browser.
Adds many new Gestures like two and three finger swipes, three finger tab, shake...
Assign different actions to the gestures like switch tabs, go back, go forward, create new tab close current tab, and so on..
With this, Safari is a really intuitive and cool web browser.
Note: FullScreen has been tested to work on all iPhones and iPods running firmware 4.0 to 4.1. It also works well with other Safari extensions.
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