The thing is, all software constantly needs new updates. If not platform-driven, then security, bug fixes, etc.
The more niche (like a pomodoro app), the fewer users over which to amortize the dev costs. A lifetime fee of $1, sold to a huge audience of 100k paid users, will pay for ~1 year of a single dev in the US, perhaps 2-3 years of a developer in a low-cost country. And then where does the money come from for updates in year 4 and beyond?
Subscription payments recognize the realities that a) development never ends for most apps that are in use and b) developers are not going to be free in the future just because the publisher only charged once.
I challenge you to demonstrate the Pomodoro app that has a full time dev effort for a year, and then requires anything more than piecemeal bug fixes or maybe a recompile in that four years of support...
You have already been paid everything you will ever get paid for work you did in 2021. Next year, I want you to do an unpredictable amount of work to support the 2025 iOS. How much will you charge me? Where will I get the money to pay you? Why would I spend it on this instead of something else where I might see a return?
Similarly, in the 1990s, things like Myst and Sim City 2000 were $40 each. Shareware at the time (mostly indie) were usually $20 or less; often $5, and sometimes fun/silly things like postcardware or beerware.
