AppForge's Crossfire Targets Multiplatform Development

AppForge has developed a range of "Ingots"--controls that work in Windows while you are developing and also work on your target device. Most of the standard Microsoft controls have an Ingot functional equivalent; the Ingot list is installed into the IDE's toolbox when you install Crossfire. In my tests, Crossfire was very intuitive as it duplicated the same Windows VB.Net project-development method. I had no problems generating and debugging VB.Net programs in Visual Studio and downloading them to the Zire.

Crossfire requires a significant amount of storage space. With the Palm OS, AppForge installed more than 1 MB of programs just for libraries. If you're distributing a single app, 1 MB of memory is too much, but if you're deploying a large number of apps, the storage use may be justified because those apps would reuse the support libraries. If you deploy five or more applications, the overall space used would be roughly equivalent to the space you'd consume if you developed using PDA vendors' libraries.

AppForge charges no royalties. However, there's an annual $500 fee for redistributing Booster if you're an independent software vendor, and there's a per-seat licensing scheme for enterprises.Counting Quirks

Crossfire lets you capitalize on your organization's VB.Net experience to develop mobile applications, but there are some caveats. I found that conversion of support files is too tied to Microsoft-specific formats. The image-conversion tool supports only .bmp files, even though the .Net environment supports most Internet graphic formats. Database conversion is available only for Microsoft Access (MDB) databases, though few enterprises store significant amounts of data in this format. I had to convert all graphics files and database data, then convert them again to the target platform's format.

And converting databases is time-consuming. In my tests, I had to export data to a flat file or directly to .mdb format and then convert it to the format the target platform requires. With graphics, each conversion introduced some amount of loss. I'd like to see AppForge develop a complete toolkit that supports all the "normal and usual" data sources and image formats.

I'm also disappointed that the product supports only Visual Basic. Since the release of the .Net Framework, C# has become a popular development language in the Microsoft arena. AppForge says C# support is coming.

Worth a TryOverall, if you run a Microsoft shop, Crossfire will give you a level of productivity out of the box that you can't achieve in normal mobile development environments. Competitors have yet to combine the ability to multitarget applications with the same source code with the benefit of reusing your staff's VB knowledge. Having the same code run on a cell phone and another vendor's PDA is a huge advantage for both enterprise and independent software developers.

Don MacVittie is a contributing editor to NETWORK COMPUTING and application engineer at WPS Resources. Write to him at [email protected].