Inaccurate readings in regards to battery, storage, and app usage.

Has anyone experienced inaccurate readings? Iphone 6 will "die" at 12%, storage is greatly miscalculated with system taking most of my storage somehow, and offloading apps considers every app "unused" and will delete everything if enabled.

Inaccurate readings in regards to battery, storage, and app usage.
 
 
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