We're looking to build a simple 2-way SMS interface that works with Twilio, via their API.
Here's how the flow should look:
1) We log into the app that you create with a username and password
2) We enter mobile numbers to send outbound messages to (UK only)
3) We enter a text message to be sent to those numbers, and it will display from a shortcode word, instead of a mobile number. The text will be powered by Twilio.
4) Inside that text message will be a regular UK number (purchased from Twilio) and the recipient can start a 2-way text conversation with that UK number.
5) A full 2-way conversation can then be had, received and sent via the app that you build.
The app has to be highly functional but it doesn't have to be aesthetically pleasing.