HTC One Remix - Manual (Page 122)

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
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.
122 Phone calls