You've already created an account and you now want to sign in to the app.
iPhone download link: https://apps.apple.com/us/app/playground-school-management/id1486661197
Once you download the app onto your phone, you can sign in using the login you created when you signed up for the app. Open up the Playground app on your phone and you should see the following screen.
Enter your email and password. If your email is not properly formatted you will see a red outline letting you know that you entered it incorrectly.
Press sign in once all of your information has been entered.
If you get an error saying that you have an invalid password or that your email cannot be found, double check your email is correct and that your password is correct by pressing on the "eye" icon on the right side of the password input.
If you forgot your password, check out our guide on resetting your password.