Ah OK I figured, but your reply was quoting the original post in this thread, which was about QuadStream. Regardless, the same answer applies to both apps. 10 devices registered to the same AppleID (or Google Play Store) can all run them at the same time. You'd only be limited by the number of concurrent streams or tuned channels you're able to feed each device. Although Channels DVR's "tuner sharing" helps quite a bit in this regard...
FWIW as of today the Multiview app now supports Dispatcharr channel collections as virtual HDHomeRun feeds. And the new “PIP mode” is implemented very elegantly.
More good news for multiview enthusiasts, YouTube TV has been improving their offering:
I'll believe it when I see it. They're waiting to do this next year? Why can't they do it now like DTV Stream? Make it make sense
Sounds like some bizarre vaporware
We need a new name for this when Google's involved. They implement it then can it after a few years, and it ends up in the Google cemetery.
Huh? DTV Stream doesn’t offer fully-customizable Multiview either. They do have an assorted of “mixes” to choose from — just like YouTube TV does.
@Jean0987654321 it is not fully customizable, they just added more mixes: DIRECTV Adds Seven New Multiview Mix Channels to Its Streaming Service
Which is the same setup that YTTV currently has.
But now YTTV is adding full mix-and-match customizability: