SMS feature is now available to all users. To set up your SMS notifications, please click on Settings > Notifications on the dashboard.
To find out more about text / sms feature, go to Text Messaging Now Heading You Way.
Learn how to set up your SMS with tutorial guides on:
How to sign up for text / sms account with Twilio
http://www.detrack.com/tutorials/how-to-sign-up-for-text-sms-account-with-twilio/
How To Set Up Email and Text / SMS Notifications For Twilio
http://www.detrack.com/tutorials/how-to-set-up-email-and-text-sms-notifications-for-twilio/
How To Sign Up For Text / SMS Account with Nexmo
http://www.detrack.com/tutorials/how-to-sign-up-for-text-sms-account-with-nexmo/
How To Set Up Email And Text / SMS Notifications For Nexmo
http://www.detrack.com/tutorials/how-to-set-up-email-and-text-sms-notifications-for-nexmo/