DeLorme Street Atlas has run on Palm OS and PocketPC (now Windows Mobile) since their 2004 edition. That was a separate piece of software from the PC package. The current version of Street Atlas includes the mobile software. You copy maps, waypoints, and routes from the PC onto your mobile device, and whatever GPS you can connect to the device can be utilized by the software, whether it's cabled, Bluetooth, or internal receiver. Street Atlas is about 60 bucks, I think, maybe not even that. You have to have a PC running the package in order to get map data onto the handheld.
For free you can install Google Maps Mobile, and as long as you have a cellular data connection, or wi-fi Internet access, you can get Google maps, along with satellite imagery, and again, it uses whatever GPS you can connect to your device.
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