System Data on an iPhone refers to caches, logs, and other resources currently in use by the system. It includes temporary files and other elements that don’t strictly form a part of an app’s storage. This category is a catch-all category and can consist of various logs, temporary data stores, and other elements that arent strictly considered part of any of the listed apps. System Data can fluctuate according to the system needs, which means that temporary data can be written to the storage as System Data and removed when iOS doesnt need it anymore. However, the problem is that you cant see what the types of data used in this category consist of, nor can you delete it.
To check the amount of System Data on your iPhone, go to Settings > General > iPhone Storage. You will see how much storage is being used and get a color-coded breakdown of the categories of data that your phone is storing. System Data can occupy a substantial portion of your phone’s storage.
There are a few things you can do to cut down the amount of System Data being used, and they vary in severity of what you have to do. For example, you can try clearing your Safari caches by going to Settings > Safari and choosing Clear. You can also try deleting apps that you dont use or offloading them to free up space. However, keep in mind that you cant get rid of System Data entirely, but you can sometimes reduce its size.