Last week I spent some time understanding how Application Verifier works. For those who have never used Application Verifier, its a great free tool from Microsoft, that can detect memory leaks (heap/handle or resource leaks) in native Windows CE/Mobile applications. It not very hard to use, especially once you have the proper setup. You will need the following along with your regular application development environment:
1. Windows CE 5.0 Test Kit : Check this out here http://go.microsoft.com/fwlink/?LinkId=71619
2. Application Verifier Tool for Windows Mobile 5.0 : Check this out here http://go.microsoft.com/fwlink/?LinkId=71622
Although the Window CE 5.0 Test Kit contains the Application Verifier Tool, its binaries are not compatible with Windows Mobile 5.0 or later. For this reason you may need to replace the Application Verifier binaries in the Test Kit with the Application Verifier for WM 5.0 (in point 2 above).
And about the usage of this tool, there is a great Virtual Lab and an offline article.
Offline Article: http://msdn.microsoft.com/en-us/library/bb278113.aspx