How can I change the default dialer app in Asus zenfone 5. I tried Settings → Apps → All, then selecting the phone app. There was a Clear defaults button which was greyed out.
Do I have to get root access to change it?
The purpose of it is to automate a conference call using uiautomator and adb shell. For this reason we are supposed to have a same UI for all devices so that we can automate it easily.
But right now, even when I call with Truedialer I get this default screen that I used earlier. The resourceid is com.asus.asusincallui:id/holdButton.
(Click image to enlarge)