>> Didn't Apple say basically "if you can sign up in the app, you need to be able to sign up in the app in a way we get a cut". So as long as linode doesn't take on new customers in the app, no problem?
> However, Apple does require that if a publisher chooses to sell a digital subscription separately outside of the app, that same subscription offer must be made available, at the same price or less, to customers who wish to subscribe from within the app.
> So no, any SaaS that can take on new customers on their site has to give their iOS app the same ability at the same price, with the requisite 30% cut to Apple for those subscriptions. They don't get to choose to not offer it at all.
This is more about content than about access. I could certainly be wrong, but Apple's not after SaaS, and probably isn't even after content-rental services (e.g., Netflix or Hulu).
The updated guidelines talk about content that is sold outside of the app. (11.6, 11.9, 11.12, 11.13, 11.14). The developer agreement has attachment/schedule 2 for In App Purchases. IAP can't be used for goods or services that are used outside of your iOS app; the wording is very precise (schedule 2:1.1). I would read that as Linode and similar services being 100% in the clear because they aren't even allowed to use IAP.
Subscriptions are a little more fuzzy; both content and services are allowed for subscription (schedule 2:2.3), but rentals through IAP aren't allowed (same). This suggests to me that services like Netflix and Hulu are pretty safe, but it's not as clear. Services in general are pretty clearly only intended for services that are intended primarily to be accessed through your iOS devices (the example provided is turn-by-turn map services). Schedule 2:2.3 also makes a limited exception to 3.3.9 of the main agreement for content-app data collection.
The official agreement seems to say nothing about equivalent offer practice (what you offer outside the app for purchase or subscription must also be offered inside the app), but that could be that I just don't know the right legalese.