Port Spliter is software from GPS Meter, and is used to share one Serial COM Port between applications, in our case, share GPS between navigation software.
You can download the version for your OS in this page
[Please Register or Login to download file] Windows Mobile 5
Windows Mobile 5 SmartPhone
Windows Mobile 6
Windows Mobile 2003
Windows CE 5
The GPS Meter is also a good tool, that could be used to Measure using a GPS. Using Port Splitter, you can use GPS Meter and your navigation software at same time.
Hope this helps.