In the event that you want to check your hair, make sure that you don't have anything in your teeth, or make sure that your make-up hasn't been accidentally smeared, it can be handy to have a pocket mirror on your person.
A lot of people use the front-facing camera on their iOS device as a pocket mirror, and a new free jailbreak tweak dubbed ayna
by iOS developer ravirajm makes it even easier to access the front-facing camera from the Lock Screen.
Normally when you swipe up on the Lock Screen's Camera Grabber, you are presented with the interface for the rear-facing Camera. Then you have to wait for the camera to load, and then you have to tap on the button to switch to the front-facing camera, and then wait for the camera to load again.
If you want faster access to your front-facing camera, ayna makes it so that you can tap and hold on the Camera Grabber on the lock screen, and you'll immediately have access to your front-facing camera so you can use it as a pocket mirror.
Whats more is ayna gives you a completely clutter-free camera interface. The whole display will be dedicated to the camera, so there is no shutter button, Camera Roll button, or anything else to get in the way. There will be a small yellow triangle at the bottom of the display that you can tap on to return to the Lock Screen.
If you want to give ayna a try, it's available for free right now in Cydia's BigBoss repository. The tweak is compatible with iPhones and iPod touches, but not iPads. It requires that you have iOS 7 installed. The tweak has no options to configure.
iOS 7.0-7.0.5, iPhone or iPod touch
iPhone 5 running iOS 7.0.4