Before you begin these steps please be sure you have already followed the steps in the Set up sending from another email account KB article. If you have not yet performed these steps, the following directions will not yield the correct functionality.
- When you are composing or replying to an email in the Android app you can tap the email address in the From field at the top and select the email address you want to send as.
It should be listed as "Send mail as: <email address>"
- Tap the address to select it. Your email will now be sent out as that address
Please note: You will need to change your From address each time you compose a message from your Gmail app