2. Open the K9 app and manually set up your personal email account as the default account by simply adding your personal email account details;
3. Now you can add your Google Apps email account. Start by clicking the "+" button. Type in your full email address and password. Click "next" and choose "IMAP."
4. This is where it gets tricky. Here's what you should change the settings to.
Incoming server settings
Username: Name@(Your Domain).com
Password: Make sure password is correct
IMAP Server: imap.gmail.com
Security: SSL/TLS (always)
Outgoing server settings
SMTP server: smtp.gmail.com
Security: STARTTLS (always)
5. Click next and set up your individual preferences.
And that's it. Obviously, I only talked about Gmail accounts. I only use Gmail accounts. I have a couple of old Hotmail accounts and a Yahoo email account that I have synced with my personal Gmail account. I no longer use my Hotmail or Yahoo email account so I have not tried to set up those accounts on K9 so I don't know if you can even do it.