>Zuckerberg also criticized a change in Apple’s upcoming iOS 14 operating system for iPhones and iPads that would make it much harder for companies like Facebook to target people using those devices with ads. Zuckerberg estimated that Facebook’s ad targeting on iPhones and iPads would lose about 50% of its effectiveness once iOS 14 was released and suggested that if Facebook could distribute its apps outside the App Store, it could avoid that kind of scenario.It's scenarios like the above from a powerful company like Facebook that would make them financially incentivized to put their own Facebook App Store on iPhones. That way, they can program their iOS app with any invasive techniques that hurts the user. To counteract that, I prefer that Apple be the only approved app store.
Although I don't use Facebook, my family in other countries are dependent on Whatsapp to communicate and I'd rather have Facebook/Instagram/Whatsapp all get vetted by Apple's approval process than Zuckerberg's self-serving team.
As for the common counterpoint of "giving iPhone customers the _option_ of alternative app stores does not affect me at all because I can choose to only use Apple App Store" ... that's not true. The part missing in that argument is that some companies (e.g. Facebook) with essential apps are very powerful in relation to the individual smartphone customer. To counterbalance that force, Apple is one of the few corporations big and powerful enough to push back against Zuckerberg. (E.g. previous examples: [1][2])
Yes, I know the majority of HN developers want control of the "device I they own" and I understand that. However, they don't speak for everyone and the iPhone is also something I own and it works better for me if influential (and sometimes shady) apps are not purposely pulled off of Apple's App Store and put into a Facebook App Store, Uber App Store, Buzzfeed App Store, etc.
For my home desktop pc, I can load any software I want and I prefer that control. However, I don't think it's a contradiction that I prefer my iPhone to be locked down.
EDIT to reply: I don't work for Apple and can't control what they do. Apple may open up the iPhone to other app stores or they may not -- without my permission. Therefore, stating my preference for iPhone policy does not restrict others' freedom. Also, my family depends on Whatsapp to earn money so alternatives such as Telegram, Signal, etc are irrelevant because their business relationships already use Whatsapp.
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Examples of Facebook abusing its internal testing account:
[1] Apple blocks Facebook from running its internal iOS apps (theverge.com): https://news.ycombinator.com/item?id=19035834
[2] Apple leaves Facebook offices in disarray after revoking app permissions (theguardian.com):
https://news.ycombinator.com/item?id=19044728