Embeddable document store database [closed]
UnQLite is a in-process software library which implements a self-contained, serverless, zero-configuration, transactional NoSQL database engine. UnQLite is a document store database similar to MongoDB, Redis, CouchDB etc. as well a standard Key/Value store similar to BerkeleyDB, LevelDB, etc.
UnQLite is 100% hand-coded, written in ANSI C, Thread-safe, Full reentrant, compiles unmodified and should run in most platforms including restricted embedded devices with a C compiler. UnQLite is extensively tested on Windows and UNIX systems especially Linux, FreeBSD, Oracle Solaris and Mac OS X.
Actually CouchDB is not strictly server-oriented. It's intended to run on a variety of environments. See here for couch on mobile.
Erlang, CouchDB’s implementation language has been designed to run on embedded devices magnitudes smaller and less powerful than today’s phones.
From http://guide.couchdb.org/draft/why.html
Tokyo/Kyoto Cabinet is written in C++, but is a simple key-value store.
See the complete nosql list for other alternatives: http://nosql-database.org/