Run only on SD card

Can I run Umbrel on only a 256GB micro SD card? It has a read speed of 130MB/s and I’m just going to run about 10 apps (Like Uptime Kuma and MeTube), nothing heavy. So is this possible or not?

YMMV…but…

When I tried to install Umbrel 1.0.x on a new RPi 5 with a micro card and a NVMe based SSD it installed and ran just fine, but it did not see and mount the NVMe SSD. So, it seems that it was running just fine off the Micro SD card. I have no idea though of how the various apps the Umbrel folks have built for their implementation react if they can’t find a secondary “data” drive.

This is one of the many things that should be publicly documented for their user base. When a “product” is put out in the wild as a “production release”, there ought to be documentation about how it works. Maybe Umbrel is working on such a document behind the scenes, but if they’re claiming 1.0 status it should already be there.