exKey add a new row of buttons on the keyboard
The tweak is called exKey and, as mentioned just above, you add a row with symbols in order to save time for their inclusion.
Thanks to exKey, if you use the keyboard letters in the mode line will show the extra numbers, but if you will use the numeric keypad will appear symbols. Nothing could be more simple and immediate, as well as useful.
If you want to try the tweak exKey you can go in the BigBoss repo on Cydia and purchase it at $ 0.99, then install on your jailbroken iPhone or iPad.