In-Product Registration
In-product registration provides a one-time prompt above the Grammarly button in your app, asking users if they’d like to sign up for a Grammarly account and get Grammarly suggestions everywhere they write.

How it works
The behavior of the in-product registration prompt depends on whether user feedback is turned on. If surveys are turned on (the default), the pop-up to register will only appear once a new user completes a survey that rates Grammarly four stars or higher. If surveys are turned off, the pop-up will appear once a new user accepts five suggestions from Grammarly.
Clicking the Get Grammarly link in the pop-up takes the user to a new browser tab where they can register for Grammarly.
The in-product registration pop-up disappears as soon as the user clicks anywhere outside of the pop-up. Once shown, it won’t reappear unless the user visits your application from a different browser.