As of today I’m officially suspending sales and support of Mint and Fever. But! As self-hosted software, absolutely nothing changes and you can continue using both Mint and Fever as you were yesterday.
I started using Fever after the demise of Google Reader, it was self-hosted and worked extremely and had some cool features to manage my RSS feeds. It even gained a decent amount of 3rd Party app support for synchronisation and offline reading despite the API being in a beta state. Sadly once Anthony Drendel stopped development of Sunstroke for iOS, the fastest of those apps, I had to find an alternative.
Sadly none of the alternatives performed well synchronising with Fever and most of the time they were not useable. About a year ago I migrated from Fever to Tiny Tiny RSS and found a plug-in that mimicked the Fever API so it could be used with the various 3rd Party applications. I now use this configuration with Reeder on both macOS and iOS, synchronisation is lightening fast and I can now get to browse through my RSS feeds wherever I am in the world.
My main concern now is that if these 3rd Party app developers see the demise of Fever then they may remove the support for the API, leaving me hunting for yet another solution.