Twiitter and facebook is very slow to open and after to open!!!!???
I did restart my device, also re install the app but both have slow start up after update in ios 7!!! You believe with update of apps fix this for iphone 4??!!
This issue was resolved for me with Twitter about several updates ago.
Good Luck
You should consider erasing all content and settings. My 4s was running super slow but after doing that it is running much much smoother now.
How to erase all contents without delete the app????