Can Umbrel apps be installed on StartOS?

There are a few apps on the Umbrel site that peak my interest and as I learn more about StartOS, I’d like to try running them.
Is there a guide on how to download apps and install them?

The short answer is no.

Umbrel apps are packaged for Umbrel. For StartOS, services to be packaged for StartOS. Many of the Umbrel apps like bitcoin / lightning nodes, nostr relays etc are also packaged for StartOS and available in the Start9 registry or the Community registry.

If there is a particular Umbrel app that you want that isn’t already packaged for StartOS, you can request the app developer to create that package, or even package it yourself (Start9 | Service Packaging).