I think something like WebOS would make a lot of sense, where the OS can use PWAs as first-class apps. This would mean developers wouldn’t need to specifically develop for it, and it would have a significant functionality from day 1, at least for the basics most people use.

This assumes the websites themselves don’t screw it up with a bunch of splash screens and gates to force users to iOS/Android apps. It’s not just an issue of Apple and Google having a duopoly, a ton of websites actively maintain the status quo and make it difficult for other players to enter the market. There really needs to be legislation to prevent sites from artificially locking users out of the mobile web experience.

I think you'd have to also support Android apps or something somehow otherwise it's not going to support the apps people rely on and few people will adopt it.

The app stores are a big moat today.

> That includes a new app store

Just as long as using the app store isn't required.

It could be Purism, which have already created Librem 5 with its PureOS Store offering free software. My daily driver btw, https://puri.sm/products/librem-5.

Since it runs a desktop GNU/Linux, you can develop and run the same app on mobile and desktop with some adjustments in the interface. It already works well with Firefox and Gnome software. Web apps work too.

The best positioned is Valve/Steam but Nvidia could do it too or Meta.