'Homekey Hangup' Lets You Use Your Home Button to End a Phone Call
Whenever you're in a phone call on your iPhone, you can end the call by tapping on the end call button at the bottom center of the phone call interface, as shown below:
For a different way to end your phone calls, you can use a jailbreak tweak called Homekey Hangup
by iOS developer Mohamed Marbouh. The tweak allows you to choose between tapping on the hang up button, or pressing your Home Button to end the phone call.
This removes your ability to use the Home Button to background the phone call to multitask and makes it so that the call ends instead.
It's worth noting that this does not work for FaceTime or FaceTime Audio calls, but only for phone calls through the iPhone's Phone application. The developer also notes that it will not work if you're using speaker phone, or have headphones connected.
There are no options to configure for this tweak. Once installed, it starts working for you right away. If you want to give it a try, it's available in Cydia's BigBoss repository for 99¢.
iOS 7.0-7.1.2, iPhone
iPhone 5 running iOS 7.1.2