RapidSMS is a free and open-source framework for dynamic data collection, logistics coordination and communication, leveraging basic short message service (SMS) mobile phone technology.
“A.nnotate lets you share and store notes on documents. When you upload a document A.nnotate displays it in the browser and lets you add notes and tags to specific words, phrases and regions of the page. You can share documents so that other people can add notes and replies. All notes are added to your personal document index.”
Features are: Private storage for documents and notes, On-line annotation of the documents you upload, Shared documents and folders so you can invite others to view and add notes to your documents. Indexes of all your documents and notes with searching and sorting by tag, author, note text etc. News and notifications about changes to shared folders and documents.
A.nnotate tries to focus on “ease of use and universal availability for the core concepts of annotation and collaboration.”