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MapTap: the handheld atlas

MapTap Atlas is easy to use. Simply choose your atlas, choose what information you want to display, and use the screen to pan and zoom around.

MapTap Atlas version 2.2 was released August 28, 2003.

Installation (quickly)

Install maptap.prc, mathlib.prc (if not already installed), and all of the -Zmap.pdb files in this directory onto your handheld.

If you are upgrading

The file format for MapTap Atlas's data files changed beginning in version 2.0. You will need to remove old versions of these files and install the new ones. The easiest way to do this is to delete MapTap Atlas 1.x and then install the current version. If you do this, though, you'll need your original Unlock Code for version 2.2. If you can't find it, send an email request to and ask for a reminder.


There are three parts to installing MapTap Atlas: the program itself (maptap.prc), a math library (mathlib.prc), and some map data layers (with names ending in -Zmap.pdb). Your handheld might already have mathlib.prc on it; if it does, there's no need to install it again.

The map layer files you choose will determine what sort of maps you can make on your handheld. You can always add map layer files later, or delete files that you're not using.

The map layer files in this directory folder are the ones we think you will want first. The USA supplemental folder contains more detailed information for the USA: highways, railroads, smaller cities, county boundaries and names. You can install any of the files; they are grouped into a directories only for your convenience.

The -Zmap.pdb files should only be installed directly to your handheld, not to expansion memory cards like Secure Digital and Memory Stick. For files that will work on your expansion cards, use the files from the expansion card only folder, which have names ending in -Mmap.pdb. Or you can download the VFS Data Installer:

For best results, keep your frequently used map layers on your handheld in internal memory, and keep all of the map layers on your expansion card. MapTap Atlas will automatically use the version in internal memory if it's available, but will find the expansion card version if needed.

The MapTap data buffet has a list of all of the layers, how they were made, a picture, and a link to the original map data. From the Data Buffet you can download a single map layer whenever you need it.

Trial period

You are permitted to use MapTap Atlas free of charge for 10 different days. After that, a license fee of $24.95 is required. Pay for your license electronically at the place you downloaded it originally.

Quick start

When you launch MapTap Atlas the first time, you'll see a copy of the license agreement, and a note about your free trial period. After you read and accept the license agreement, you'll see a note about data files to unpack. These are the same data files you installed earlier, but they need to be converted before MapTap Atlas can use them. Tap "OK" to unpack them.

Then you'll see MapTap Atlas's home screen. Tap "Draw" to draw the Digital Chart of the World.

When the drawing is complete, tap "Show..." to see the controls for your map.

Tap the "+" key a couple of times to zoom in.

Tap "Show..." again, and tinker with layer selections. You have your choice of city populations and other data.

Tap on the map near Corsica and zoom in for a better view. The "Thin?" checkbox shuts off names of smaller islands and countries, but you sometimes will want to turn off the thinning.

You can set the map window directly by tapping "Goto...". Then either enter the latitude and longitude of the center point, or choose a state or country by name from the popup list. Here's a quick way to get a map of Liberia:

Tap "Atlases" to go back to the home screen. If you then tap "US National Atlas", you'll see similar controls for the United States map.

Map projections

You can choose the projection for any maps you create with MapTap Atlas. Here are 3 different maps of the United Kingdom, each with a different projection.

Now you're ready to use MapTap Atlas.

Data sources

USA files are reduced resolution versions of data files from the US Geological Survey's National Atlas. For the original data, in standard GIS formats, see their web server. Most of the original data was at scale 1:2,000,000, but has been resampled to an even smaller effective scale for use in MapTap.

World files are reduced resolution versions of the NIMA VMAP Level 0 data, formerly known as the Digital Chart of the World ( City data makes use of population figures from the World Gazetteer (, (c) World Gazetteer, used by permission.

Links to the original data sources are at the MapTap Data Buffet.

Copyright 2003 Mobile Geographics LLC. Redistribution prohibited.

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