@supremus This is more an explanation of how I understand the pricing of Ivory came to be, based on following the developers on Mastodon.
My understanding is that Tweetbot, which was available for a $6.99 annual subscription from my memory, was a large part of Tapbots income. When Elon Musk pulled the plug on third party Twitter apps, Paul & Matt (of Tapbots) felt it. Ivory was not planned to be released so early as there are still many features missing. Users on Mastodon of the alpha/beta were telling Tapbots to go ahead and release the app as it was. They were willing to pay for it. They also said that they thought that Tweetbot’s fee was too low. Paul published what they were thinking to charge (what you see now) based as I understood it on the feedback that he had been receiving on Madtodon, and the feedback was overwhelmingly supportive of the prices. For now the $25 is just if you want to say a big thank you. You get nothing special at that price.
Development has been swift, Tapbots have done well in getting the app out there in a short time, and they have a faithful following built up upon years of software development (especially Tweetbot). I’m paying for this year, supporting the developers, and keeping my eye on other apps like Ice Cubes which is free (tips appreciated).