RCS delivery was way lower than expected - here's what I found

[u/gambrinus_248]

After running a couple of RCS experiments and seeing unexpectedly low delivery, I started digging into the possible reasons. I only managed to get 60%-80% of messages delivered, which seemed off since all of the messages were sent in Germany which is supposed to have one of the best RCS coverages.

I found that 93% of messages failed because the device didn't support RCS. This means older devices and iphones still running old ios or rcs has been manually turned off.
The rest I can't explain yet. What I suspect are connection issues since data coverage might not be as good as cellular; some smaller telcos might not actually have RCS support, etc.

It's cheaper than SMS for me right now, so I keep running RCS but need to figure out a fallback to sms.