[gojomo]

Because outside the App Store, Apple doesn't get their cut, and external payments or software-deliveries don't bind people to the habit of App Store purchases and in-app purchases.

With this pseudo-upgrade process, even as convoluted as it is, it all remains inside Apple's system.

I suppose the key question is: does Apple allow promotions that give some people the same effect as in-app purchases, while others still have to make the paid purchase? (I think they do.) I could see Apple objecting if the feature-turn-on is in any way a reward for outside-of-App-Store valuable behavior - that's circumventing Apple's role.

But if it's an extra bonus for an earlier in-App-Store action – the N-1 version purchase – Apple's role hasn't been circumvented. In a way, it's been reinforced. So the same logic driving the prior veto wouldn't apply.

[timeuser]

Perhaps. It's an interesting theory. I've seen it claimed in the past that Apple has given explicit permission to activate in app purchasable features through other means such as contacting a developer's server with an unlock code. I'm still leery of going through the effort to build and support a kludgy solution like that and still have the risk of Apple not approving of it.