SatNav Software for PDA's

Hi, I'm doing some research or the company I work for in regards to PDA's a sat nav systems. We need a multi-purpose pda that can run third-party applications (sales database software) and hopefully sat nav software for our salesforce team.

I've been looking around but apart from all purpose sat nav systems there seems little in the way of specific sat nav software, except tom-tom, that can be loaded independantly on to pda.

Can anyone recommend any third-party sat nav software, apart from tom-tom, as an alternative to this product . Any help would be greatly received.

Thanks.

[Stevie]

There are many Sat Nav software systems out there like:
Destinator GPS
Garmin
Navman
Kane
INS
MemoryMap GPS
Wayfinder GPS
P-Link GPS
Route 66 Mobile