Build an app that lets users send text messages to their friends. ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
[+] As a user, I want to send a text message to a phone number, so that I can send texts from the web. Hint: Follow along with the lesson.
[+] As a user, I want to save contacts to an address book, so that it's easy to text them again without re-typing their phone number.
[-] As a user, I want to send a message to more than one person at once, so that I can mass text my friends.
[-] As a user, I want to send pictures in my messages, so that I can share photos and cute cat pics with my friends. Hint: Check the Twilio API docs.
[-] As a user who receives a text message, if I text back, I want to get an automated response telling me that the phone number can't receive texts, so that I don't get sad when the sender doesn't reply. Hint: This will be a bit hard, and I don't expect you to necessarily finish this.