It's a bit sad though that games that use in-app purchases in a good way are mixed in with the "freemium" games. One example is Smash Hit, which you can try for free and if you like it, a one-time in-app purchase enables features such as iCloud sync and checkpoints.
Yup, or Monument Valley, which has a one-time unlock for the additional levels. There are lots of games like that. It would be nice if Apple distinguished between consumable IAPs and unlockable content. However maybe there's too much gray area between the two, so it probably does make the most sense for Apple to just keep it simple. Hopefully Apple keeps this category around in iTunes, and it will encourage developers to develop pay-up-front games.