HTC One - OS 4.0 - 4.1The image below is of the Samsung Galaxy s4. I don't have access to one of the phones but AT&T has some support pages that will help you with email and connectivity. Below are links to some of their tutorials. The image below will show you where you need to tap to begin their tutorials. Hope this is helpful to you.
Email - Personal - Corporate - Send & Receive - Options - Delete Account
Connectivity - Wi-Fi (turn on & off) - Cellular - Hotspot - Tethering - NFC
Public & Private Hotspots- Mobile Hotspot - Bluetooth - Bluetooth Pairing
Other - Master Reset - Android Version - Text Messaging - Send a Text Message