There are two types of MuseScore subscriptions: trial and non-trial (instant).
Trial subscriptions provide 30-days (7-days for the mobile app) free access to PRO features and the ability to use almost all functions available on the website and in the mobile app.
Non-trial works for those who like to pay less and get access to all premium features in a flash.
You can choose which option suits you and add, change, or edit your subscription details at https://musescore.com/user/settings/profile.
To learn the exact subscription price, please, click on 'Go PRO', 'Try for free' or 'Start Free Trial', as prices vary depending on the currency.
Please note that one PRO subscription can be used on the website and in the Mobile App.
To access your Pro account in the mobile app, simply close the windows that suggest starting a subscription by tapping 'X' or 'Close' at the top of the screen and proceed with login.