There are also several commercially available systems that
focus on collaborations on Apple portable hardware. Crowd-Map from Barking Minds, allows users to build mind maps
collaboratively on their iPads or iPhones. The tool, which
operates in real-time, has been designed for the organization
and sharing of mind maps within working groups. Another
system that makes use of `live' collaboration using iPads and
iPhones is letsannotate that allows users to view and annotate PDF files. The portable iPad version is currently only
in its beta stage, and does not run as an application, but
through a web browser.