HTC Rhyme User Manual page 203

Email 203
Checking your Mail inbox
When you open the Mail app, it displays the inbox of one of your email
accounts that you've set up on HTC Rhyme.
To switch between email accounts, tap the bar that shows the current
email account, and then tap another account.
Viewing the unified inbox of all your email accounts
You can view email messages from all your accounts just in one place
without having to switch to different accounts.
Just tap the bar that shows the current email account, and then tap All
accounts. Email messages are color coded so you can easily distinguish
which email accounts they belong to.