Used — Com.samsung.android.app.telephonyui

You accessed the menu during a call to change audio outputs or view a keypad.

No. Because the name looks technical and unfamiliar, many users worry it is a tracking app. However, is a legitimate, pre-installed system file. It is required for your Samsung phone to function as a telephone. If you were to disable or delete this package (which usually requires "root" access), you would be unable to answer or make calls. Common Issues and Fixes used com.samsung.android.app.telephonyui