Winforms: GPS GUI

Question

Our development team has been tasked with "creating" (or reusing an existing) GUI application that will display certain objects (be they people, cars, tools, w/e) in a certain field that could range in size between a couple of blocks to an entire city.

Generally our users divide the area off into four or more quadrents and assign other users to the quadrents to perform tasks.

Generally, we can assume that the people are going to be walking around with hand held units with built in GPS capabilities and will stick fairly close to the other objects assigned to them.

I've only been able to work with the Google Earth free edition so far and the google maps API to get the GPS coordinates off of an address, and then mark it, and zoom to it. I like how user friendly the KML language is, and I feel like I could do this entire project with that software given enough time. However, just because I've used a language doesn't mean its the best one so I need some guidance.

I want to offer options as to what software we can use to do this. We've come up with four main options so far:

1. MapPoint
2. Google Earth
3. Google Maps
4. Custom Direct X drawn GUI (Thats right, Video game style)

My question really boils down to the following:

What technology should be used to accomplish mapping multiple GPS coordinates onto a map for users to browse?

Keep in mind, the area we are talking about here can be a couple of blocks, or city sized, and mapping precision is a key factor in the decision. Our decision is not limited to one of the technologies mentioned, I just simply don't know of any other ones. Also, having satellite imagery and topographical information would be a really useful feature here since some of the landmarks may be displaced or non existent as the software is running.

Other information that would be really helpful:

1. Is the Google Earth clarity or resolution any better on pro or enterprise version?
2. Is the Google Earth local imagery cache larger than 2 GB on pro or enterprise version?
3. Is the Google Earth coordinate system more precise in pro or enterprise?
4. What would be the benefits of one technology over another?
5. If the hand helds are out of Wi-Fi range, does anyone have any recommendation on how we get its GPS coordinates?
6. Are there any major technologies that we are not considering here that we should be?

Answer 1

Just some random thoughts:

• GPS can be VERY problematic if you are within a city. That could be up to the point where you get no coordinates at all. But likely you will not get very accurate measurements. An option could be to combine WiFi location and GPS location services.
• "5.If the hand helds are out of Wi-Fi range, does anyone have any recommendation on how we get its GPS coordinates?" I'm not sure what you mean by that? GPS itself is not limited by any Wi-Fi range.
• I don't see how DirectX will help you if Mappoint or even Google Maps is an alternative. Neiter of those are particulary fast and you can reach the same EASILY by usual drawing techniques.
• The corrosponding MS-stuff for Google Maps is Bing Maps which you didn't even mention (http://www.microsoft.com/maps/)

P.S. Maybe it would have been better to ask multiple (but more specific) questions.