Talking about Signal Foundation (and the signal app) more than Mobile coin.
I think this is an incredibly bad idea for the Signal Foundation to add MobileCoin or any Payment Service into their app. It’s not just bloating of what was a clean secure communications app. It’s not even that Signal is choosing to tie itself to a specific blockchain currency.
Adding a cryptocurrency to and end-to-end encrypted communications app muddies the morality of the Service, and invites all sorts of government investigative and regulatory meddling; by the IRS, SEC, and probably the FBI.
I see no good reason to do this. Secure communications and secure transactions should be separate apps.
I personally don’t use MobileCoin for this reason.
Also, in one point of the History of MobileCoin if you were U.S. Citizen. You weren’t allowed to use MobileCoin in their terms of service. I don’t know if this true today, I haven’t looked.