Twilio and Google App Engine were used to create a new application called SwapCard, which allows users to send virtual business cards via SMS. The app was built by Robert Do, Product Marketing Manager at Google Cloud Platform, as he wanted to solve the problem of not having business cards on him when meeting someone. He found it easy to get started with Twilio and App Engine, and was able to deploy his app in a matter of days. The app works by texting an email address to a Twilio number, which then forwards the message to an App Engine app that sends an email to the original email address. A confirmation SMS is also sent back to the user. To set up the app, users need to register their application at Google Cloud Platform, create a project, and deploy their own App Engine app with webapp2 framework. They also need to sign up for a Twilio account and set up a phone number that points to their app whenever it receives an SMS.