There's a few apps that I liked that were completely pulled—not just unable to be purchased, but also, you can't re-download them if you had already bought them

There's a few apps that I liked that were completely pulled—not just unable to be purchased, but also, you can't re-download them if you had already bought them. One got pulled because the developer was hired by Apple, and one got pulled because the developer was bought by Facebook. And certainly a whole ton more that just... don't exist anymore, so I can't see them to be reminded of them. Another thing that happens is apps that get steadily worse over time. Bad Piggies was one of the best iOS games I've ever played, but it got stuffed with obnoxious ads, and the experience of playing it is considerably worse than it was just after release.