Hi everyone, dev evangelist at TelAPI here. If you have questions or thoughts you'd like to share, feel free to let me know - thanks!
2. "Unblock caller ID"? You mean, perform a CNAM lookup on the number? If a caller doesn't send a number, that's sorta that. I'm guessing you're just referring to the flag "hey please don't display the number or lookup a name", right?
As far as setting caller-ID, that's great. Do you have a plan to deal with abuse, which is why I imagine Twilio disables it for the masses? (Not that it's hard to do at all, from a technical perspective.) And of course, not available for doing with SMS.
Good luck!
1. The flat-rate is $27/mo per channel. TelAPI also offers channel bursting . This ultimately means developers and businesses have on demand access to additional channels for TelAPI numbers with unlimited inbound calls. E.g. You have 1 unlimited inbound number with 10 channels. Then you receive an 11th call. Channel bursting ensures the call can still access the application and won't ring busy.
2) CallID unmasking allows developers and businesses to identify the number and ID of calls received from 'Blocked' and 'Private' numbers to your TelAPI number
Our parent company TelTech uses it for one of their products: http://www.trapcall.com/
What's the underlying infrastructure? :)