Since iOS manages iPhone's memory and resources almost always in a very smart way, rarely you need to close an app by yourself. But if we need, let's see how to force close an app on iPhone.
The steps you will need to take varies in each version of iOS. However, the idea is the same all the times.
- The fist step is to access the multitasking tray. Then, we see a list of the apps recently used.
- Now, find the app that you want to close.
- Then, swipe up the app's preview. This action forces the app to close.