Other apps take up more space as they have much content, e.g., videos, images, or files, to use even without Wi-Fi. As an illustration, streaming applications tend to cache the downloaded programs, and social networking applications cache images and messages. When you look at what are Applications in iPhone storage, the size changes depending on how each app works and how much you use it. Reading what is Applications in iPhone storage allows you to figure out which apps are heavy and hence choose to handle or delete them to allow your phone to free some space.