MAC VERSION:
(Note: you won't need to download anything)
1) Open Quicktime Player, it comes with you're mac.
2) Choose the option called "screen recording", and you will be able to choose where you want to start or stop.
3) When you have done you're screen recording then you should put the record on you're desktop.
4) After that, open iMovie, also comes with you're mac.
5) Select "import files" and them select "desktop" and you will be able to choose you're recording to make you're own edit.


If you want to record you're screen without jailbreaking try to search on safari emu4ios, and transfer the recording to you're mac.