JSON DOCUMENTS – Everything stored in CouchDB boils down to a JSON DOCUMENT.
RESTful Interface – From CREATION to REPLICATION to data insertion, every management and data task in CouchDB can be done via HTTP.
N-Master Replication – You can make use of an unlimited amount of ‘masters’, making for some very interesting replication topologies.
Built for Offline – CouchDB can replicate to devices (like Android phones) that can go offline and handle data sync for you when the device is back online.
Replication Filters – You can filter precisely the data you wish to replicate to different nodes.