Autodesk Instant App for iOS and Android
According to Autodesk, Instant makes it easy for coworkers to instantly communicate no matter where they are and exchange messages, photos, video, and location. Colleagues can initiate conversations with anyone in their address book, or any other colleague who has verified their email with the app.
It sounds a lot like SMS text messaging. We've downloaded and installed the Android version. You'll need to provide your cell phone number and email to sign up. Not sure what happens if you're using an iPad, iTouch or other non-phone device.