[1] https://www.sec.gov/Archives/edgar/data/1477425/000155837018... [2] https://www.sec.gov/Archives/edgar/data/1447669/000110465918...
I suspect we represent a core customer type for both firms, and I rather suspect they have a pretty extensive overlap in their client list, so some obvious synergies will be around support, APIs, account management, etc.
Fundamentally, their business is about running APIs that let them accept incoming requests from people like me, processing it, and then passing it on to some very ugly external services that will (eventually, hopefully) display a text message to someone at the far end. That's a lot of overlap!
Aside from that, Twilio can now act as almost a one-stop shop for your outbound communication needs - all that’s left is physical letters.