Woobius Eye is a free collaborative web application that enables you to mark up images while having a conversation via phone or Instant Messaging, so that you can visually illustrate your discussion or explain hard to describe details. It takes seconds to use, and no registration is necessary. Its simple interface allows you to invite as many people as you like to participate. Anyone can upload images or screenshots, one at a time, and users can annotate them simultaneously. Woobius Eye is an offshoot of Woobius, the file sharing software for project collaboration used by architects and engineers. According to the company, a mobile application will be available soon. Check out their demonstration video below.