Yes! Here's how to set this up:
Head over to https://toutapp.com/next#identities
Click the New Identity button (top, right-hand corner)
Fill in the necessary information. Make sure you enter the "Email" field - that one's pretty important!
Hit Save Changes.
You'll recieve an email shortly asking you to verify your new identity. Click the verification link to finalize the process.
Now when you go to send an email in Tout, you can toggle between identities: