Did you know that you could protect the Messages, WhatsApp or any other application or game using Touch ID fingerprint sensor? To get this functionality, you will have to install a Cydia app called BioLockdown that allows you to either add password protect or use Touch ID to launch a particular app.
For the touch ID functionality, you ought to have an iPhone 5S or iPhone 6. BioLockdown also lets you restrict certain settings which would only be enabled with your finger scan.
So if you want to prevent your friends to mess around with the settings such as disabling wireless LAN, you should search and download BioLockdown from Cydia. It is totally free and the only requirement is a jailbroken iPhone.