I want to develop a system that users remotely interact with over a phone call. Like your bank's phone banking system.
This system will be very simple: when a user calls, it merely needs to prompt the user and accept input purely through the keypad. Additionally it will need to be able to receive and send text messages.
1- Are there non-proprietary frameworks out there that support this?
2- Can anyone share the basics of their experiences in deploying this kind of system? Pitfalls, what to watch out for, etc?
There is an opensource project Asterisk that will help you accomplishing this.