Xnest basically provides a X server in an X window - it being both an X Server and an X Client at the same time. This makes it useful for both testing Matchbox on a desktop machine and 'emulating' PDA sized displays. The procedure for running Matchbox in an Xnest follows:

% Xnest :1 -ac -geometry 240x320
% export DISPLAY=:1
% matchbox 

A similar technique can be used to run Matchbox locally on a development machine but have it manage windows on another display (such as a handheld). On the remote machine, make sure there is no window manager already running and then give access for the X Server from the development machine (e.g. with xhost +dev machine IP or by using Xnest with -ac argument). On the development machine set the DISPLAY environment variable to the remote machine's IP and then launch Matchbox.

Matchbox can be run under Valgrind on x86 platforms to debug memory allocations and management.

It is recommended, though not essential, that the Matchbox build is configured with the --enable-debug switch. The resulting binaries will spew verbose messages to standard out which contain information that's useful for fixing any failed tests.