The Sony Ericsson P800 is a smartphone introduced in 2002 based upon UIQ version 2.0 (which itself is based upon Symbian OS v7.0) from Sony Ericsson. The P800 is arguably the successor of the Ericsson R380, and initial design work was done within Ericsson, but it was produced after Sony & Ericsson merged their mobile phone businesses.
A long awaited updated version of the "P" series phones, the Sony Ericsson P990 was launched at the Symbian Smartphone Show in September 2005. It is based upon the UIQ3 platform (utilizing Symbian OS v9.1).
The latest successor is the Sony Ericsson P1, announced on 8 May 2007. Whilst using the same UIQ platform as the P990, it has a smaller form factor based on the Sony Ericsson M600 and updated hardware.