I am not convinced that this will add a lot of revenue for the app. My experience is that almost no one pays for software, unless he is forced to do it in a way or the other. I developed a video player a few years ago, and gave it away for free, with a donate button on the website. Although it got quite popular at some point (>10.000 downloads a month), I only made about 50€ in the 2 years where I actively maintained it. It still was a fun project but the donation stuff was completely useless. Sure it would be a bit different if the button is directly in the app. But still, with this experience, I do not believe that a reasonable number of people would press the button, unless there is at least some kind of direct benefit to it.
But your post made me think about adding one more in-app purchase, perhaps some kind of "gold, premium, ultimate edition" or whatever, with one little extra feature. So it would be a bit like a donate button, but with at least a little extra benefit added, so people get something in return for pressing the button. But only a little extra, for not to take away too much functionality from the normal users. Huh, well, I will keep that in mind.
Thanks for posting this. I think the question on app monetization is an important one, and currently there is no good answer to it. Unless something changes, most apps will stay hobby projects. The apps could be much better, but because the devs need to work somewhere else the whole day, they can only put very limited resources into the apps...
The reddit thread contained this link, which I found quite interesting:
Papering Over App Store Problems | stratechery by Ben Thompson
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