On iOS running devices, apps are organized and sorted by time of install (except the default apps). To change order and sort apps alphabetically on iPhone 5 and other iPhone, iPad and iPod Touch devices, do as follows:
1. Open the Settings app on your iOS running device
2. Go to the General settings
3. Scroll all the way down to the Reset settings and open it
4. Touch the Reset Home Screen Layout option and hit the Reset home Screen to confirm ordering and sorting the application to their default layout
Note that, after resetting home screen layout, first the default apps are sorted and then installed apps are sorted alphabetically.
Please also note that, since we are sorting the apps to default factory layout, all your created folders will be gone (just the Folders, not the content inside them)