Calling A Number In A Message, Email, Or Calendar Event; Making An Emergency Call - HTC One User Manual

150 Phone calls

Calling a number in a message, email, or calendar event

When you receive a text message, email, or calendar event that has a
phone number in it, you can just tap the number to place a call.

Making an emergency call

In some regions, you can make emergency calls from HTC One even if the
nano SIM card has been blocked or if you don't have one installed.
If you don't have a network signal, you won't be able to make an
emergency call.
1. Open the Phone app.
2. Dial the emergency number for your locale, and then tap Call.
If you've enabled but forgotten your lock password or lock
pattern, you can still make emergency calls by tapping Emergency
call on the screen.