I think it’s fair to say that we broke new ground with our iOS remote signer. People have been trying to build something like this for a long time (even predating Nostr) and afaik all those attempts have been shut down by Apple. Some of our well informed users are concerned that our implementation breaks Apple’s rules and that Primal might get banned from the App Store. I’ll share our experience here so that other builders can benefit from it.

First and foremost: we didn’t try to sneak this feature in. We provided a detailed explanation to the app store review team outlining exactly what we are doing and how. The technical tldr is: the only way to keep your iOS app running in the background is to play sound or dox user location. There is a history of developers trying to hack their way in by playing silent audio tracks or attempting to trick the reviewers (and confuse the users) in other ways.

The key to our success was that we actually built a polished ambient sound feature for our signer. Some users might actually want ambient sound for their remote sessions, so we took great care to pick the appropriate sounds and build polished UI that enables users to control those sounds via the dynamic island or the live activity UI on the lock screen. We also designed an informative sound opt in screen at the beginning of the session. This is important: the user is fully informed and totally in control every step of the way. I am not sure, but it might be helpful that Primal was already a multimedia app so this feature doesn’t feel out of place.

In any case, that’s how we did it; hope it helps other builders. 🫡