It is always advisable to occasionally scroll through your Applications storage, say once every few weeks or even when your iPhone is giving you issues of running out of space. Check what is taking up space by going to iPhone Settings > General > iPhone Storage. When you do not know what is on the iPhone storage, it has all the applications and their information that one has installed. After you check regularly, you will see the bulky apps and go ahead and delete what you do not want to use. Understanding what is Applications in iPhone storage helps you keep your device fast and storage under control.