The Mavis Camera "Buy us a coffee" In App Purchase (IAP) is a one-time Non-Consumable purchase that allows you to reward the Mavis team for using the app's free features.
The "Buy us a coffee" IAP does not unlock any features within Mavis Camera as it is purely a reward / gift mechanism.
Pricing information can be found on the Mavis Camera App Store page: https://apps.apple.com/app/mavis-camera/id979227459
Mavis Camera is available on iPhone and iPad. Terms and Conditions apply. See mavis.cloud/terms-and-conditions for full details.