One of the big reasons people plunk down their hard-earned cash on mobile devices is the freedom they provide - to work, entertain yourself, or communicate almost anywhere. That freedom rarely comes without limitations though. Buy an iPod, for example, and you can pretty much forget about buying your music from anywhere but Apple's iTunes store. Similarly, if you buy a Windows Mobile-based PDA, you can't run applications written for Palm OS devices.

Or maybe you can, using StyleTap Inc.'s StyleTap Platform, a Palm OS emulation utility that promises to let you run most Palm software on most Windows Mobile devices. StyleTap Platform works with Windows Mobile 5.0/2003 as well as Pocket PC 2002/2002, including Pocket PC Phone Edition. (A preview version for Windows Mobile Smartphone Edition devices like the Motorola Q or T-Mobile Dash is available.)

Installing Applications
The first step to using Palm apps on your Windows handheld is to install the StyleTap Application Launcher onto your PC. With it you can select Palm apps from your hard drive, to install on your device; the application launcher loads them onto your connected device via ActiveSync. (The launcher also has a batch mode so you can specify multiple applications and install them all at once.) When you use StyleTap Platform to add new programs to your device, they each get their own icons in the Windows Programs group, but you can also access any of them by running the StyleTap Launcher on the device.

StyleTap Platform should work with most applications written for version 5.2 of Palm OS or earlier, and the company web site contains a list of about 100 applications that have been certified to work with StyleTap. There's also a list of roughly the same number of programs that users have anecdotally reported to be compatible.

We downloaded a random sample of six Palm OS applications from Palm Boulevard’s downloads section and other popular sites, and tried using them with a StyleTap-equipped Cingular 8525. Our software choices included a mix of personal productivity utilities (like a foreign language dictionary and diet tracker), as well as several games. Although two of the programs refused to install, but we were able to get the other four onto the 8525 without fanfare.

Running Applications
Any Palm application you through StyleTap Platform automatically executes within the StyleTap Launcher, which provides access to the program's menu system as well as the ability to switch between multiple running applications. The applications are automatically scaled to fill most of your device's screen (or 240 x 240 on a 320 x 240 display like our 8525's).

This stretching can make fonts look blocky and distorted, and we also found that it can sometimes lead to display anomalies, like parts of the screen failing to update properly. You can avoid most of these problems by running in 66 percent display mode, which confines the Palm application to a 160 x 160 box. Doing so also seems to help applications run a bit more smoothly, though the smaller pixels of higher resolution displays can make the StyleTap window harder to see comfortably.

If you have a PDA with full 640 x 480 VGA resolution - and there aren't very many), StyleTap displays 480 x 480 by default or 320 x 320 in 66% mode. In fact, if you want to run a Palm application that requires the 320 x 320 display standard on many current Palm devices, you'll need a device with a full VGA display.

Not withstanding the two applications we weren't able to install, we didn't experience any adverse issues with the programs we could get to run. Sound functions seemed to work properly, and you can even cut and paste between your StyleTap Platform and native Windows programs. For keyboard input, StyleTap Platform maps the four Palm application keys to the standard quartet of keys a Pocket PC provides.

Things are less straightforward for devices without those keys (such as those running Pocket PC Phone Edition)—StyleTap's web site documents special key mapping for specific devices like the Palm 700w and the HP iPAQ hw6500 (but many of the mappings didn't work on our 8525).

Emulation software is rarely free of limitations, and StyleTap Platform is no exception. Most notably, it won't work with conduits, so you can't use it with programs that need to communicate with desktop Windows applications-- this includes using HotSync. Apps running within StyleTap also can't avail themselves of a device's Bluetooth hardware.

StyleTap costs $49.95. You can also take the application for a spin with a free 14-day trial. These days many major applications come in both Palm OS and Pocket PC/Windows Mobile versions, but there are still lots of custom or niche-oriented programs you can only get for Palm OS. If you'd like to run one of them on Windows hardware, StyleTap Platform may be a good way to do it.