You can easily log out of your account at any time, which is useful if you share the app with another user.
From the main (left) navigation menu, select Settings. The Log Out option appears in the Account Settings section.
Tip: Take note of the email address you've used to access the app, and make sure you use the same email address the next time you log in. Using the wrong email address happens more often than you might think, and can lead to issues (such as accessing the app but not having your data or Premium subscription appear as expected).
Once you're ready, select Log Out, then select Log Out again to confirm.
The next time you access the app, you'll see a screen similar to the one shown below. Don't try to create another account using the options near the top of the screen! Instead, select the Log in here link.
This link takes you to a different screen, where you can specify your login email address (that you hopefully noted earlier), supply your password, and re-access all of your existing account information.