iOS 6 Bluetooth problems - Apple Community
iPhone Historybattery indicator stuck at 1% - Apple Community
https://discussions.apple.com/thread/5331165
https://discussions.apple.com/thread/5575236
iPhone SE Bluetooth issues - Apple Community
Issues relating to iOS - Wikipedia
https://en.wikipedia.org/wiki/Control_Center_(iOS))
Eavesdropping - Wikipedia
Gregorian calendar - Wikipedia
iOS jailbreaking - Wikipedia
https://en.wikipedia.org/wiki/IPod_Touch_(4th_generation))