Do all Librem One services require a local client? To use Librem One on a Chromebook I would have to use the Android apps? Will Librem One become available on other arm processor platforms after the Librem 5?
Librem Social you can access via a web browser - https://social.librem.one/
Librem Chat - I asked this on the matrix channel. You could access it via the web (though that functionality is not provided by Purism), but that is not recommended, for security reasons.
I don’t have Librem Mail (I have the free account, at least until the upgrade functionality is complete). And future services (cloud etc) I don’t know.