For those that like X is like Y but for Z, I would liken us to a Heroku for telephony applications.
You can use our high level REST APIs to build high level things like a PBX (configure a device, provision it, configure a callflow, voicemail box, etc); our low-level AMQP APIs which provide lower level telephony actions (answer the call, play this file, etc); and coming soon are more real-time interactions to make it easier for third parties to integrate telephony into their existing work.
And for startups just getting going, we're offering the first five seats free (plus a phone number)! Sign up at kazoo.io and message me to get bumped up in the invite list.
I'm Josh, I run Biz Dev for 2600hz. We've built a carrier application switch in Erlang, and we have two sets of APIs (REST and direct AMQP) to allow you to do big things.
This isn't Twilio because it's open-source, massively scalable and does handset registration via API.
This isn't just another boring PBX.
This is a set of powerful APIs backed up by lots of built-in software redundancy.
If you'd like to deploy this to your servers, it's really as simple as creating an account, clicking on the cluster manager and pointing the cluster manager to your servers. Our platform handles all the setup for you.
In short, if you want to build big things in Telecom, we can help, or you can use our tools to deliver this service.
Do what makes you happy :).