I have been extremely pleased with the work Gera IT have done for my company. They have been extremely easy to work with, have delivered high quality work, and have done so at a reasonable cost.
Application provides a set of services (e.g. synchronization of data) to be used between different partner communities.
About technologies: security is based on OAuth. And the main point of this service is that all changes of user's data on one of the services (communities) s/he uses will reflect in same changes on other applications that s/he uses. Core service is a synchronization of friendship accounts, contacts and messaging on different applications.
Architecture was designed to hold one millions of requests in order to be able to synchronize activity of big set of users from popular services (like facebook, twitter etc.)