I have the default Phoner Dialer on my HTC phone as well as the Doximity Dialer. When I first installed the Doximity dialer, whenever I made a phone call it would ask which phoner dialer to use the native one or Doximity and then followed by 'Just once' or 'Always'. I made the mistake of choosing the native phone dialer and hitting always but cannot for the life of me figure out how do I reset so it goes back to providing me with the choice of a dialer whenever I make a phone call. I have gone under Apps and looked under both the apps properties but to no avail. Any help would be greatly appreciated.
Go into settings → apps. Open the menu, and select show system apps. Now scroll down to the stock phone app press on it → set as default → clear defaults. Now, whenever you select a number to call, it will ask which app to use.
If you don't see the clear defaults option, then go to settings → apps. Open the menu and press on reset app preferences this will clear all your app preferences, including which app should be the default.
Don't worry, this will not delete any data.