Depending on your phone model, tap
to see how much memory is available and how your phone's memory is being used.
You can also find out how individual apps are using memory.
Memory used by apps to find out the memory usage for apps.
Tap the current duration, and then choose the period of time you want to see.
to see the peak memory usage for apps in the list.
Tap the name of an app to see details about its memory usage.