What's that symbol and how to remove it? What's it's use.

Samsung M51 lags in camera application. So much frame drops. Looks jittery.Although it has a Snapdragon 730 g processor yet it does not perform as good as a budget Samsung phone with exinos processor.

The status bar text and icons normally switch between dark and light modes depending on the background color. On occasion however, the status bar on my phone fails to switch from one mode to the other, leaving me with white text over a white backgrou...

Waiting for three things on Samsung M511. Full Fledged Good Lock Support2. Full Fledged Android 123. Carrier AggregationWhat's your thoughts?