NOTE: The app that you wish to use as your default for email must support this feature. (If the option does not appear and you have the correct operating system, contact the app developer to request that they add support for this feature.)

1) Open the Settings app.

2) Scroll down and tap the name of the app that you wish to use as your default for email.

3) Tap Default Mail App.

4) Tap which mail app that you wish to use as your default.

Outcome

Your default email application for iOS or iPadOS has been configured.