The Open Source ERP is a web based.
The ERP server software runs on Linux. The ERP need no plugins in the browser on the client computer. The ERP can be accessed from any where with out effort. Be it at home with your home computer (Windows, Linux, MAC OS X), or traveling with your smart phone (iPhone, iPad, Android), or in the office, the data is always at hand.
Webdav interface and Active Sync for synchronizing contacts and time management.
In addition to customer, order, invoice...