tropo's got an unlimited free dev account. you might want to build something that could abstract the calls to either and switch between them as need be (twilio restructured pricing recently, tropo may do the same, etc).
I did something like this some time ago, before twilio (or at least before I knew of them) and may revisit this basic idea at some point.
I did something like this some time ago, before twilio (or at least before I knew of them) and may revisit this basic idea at some point.
good work :)