Maestro Pro
Buy Professional on this website
Go to the buy page, enter your name and email, choose £89 per year or £10 per month (a 12-month contract), and continue to the secure payment page.
After you pay, recover your licence key using the email address you paid with. We email you the key and the TestFlight install link. In the app, tap "Already have a licence key?" on the paywall and enter it.
A licence bought on the website works on up to 3 devices. You can remove a device at any time to free its place.
If you already have an active licence for your email address, the buy page tells you and links to key recovery instead of letting you pay twice.