All application servers provide a middle tier between back-end data sources and front-end clients (often browser-based, but also including standalone applications written in, say, Java or C). We found that WebObjects excels in providing not only such enterprise-level application services, but also a consistent, well-conceived integrated development environment that encourages production of reusable, object-oriented code. (For more information, see "In the Middle: Eight Enterprise-Ready Web Application Servers," at www.networkcomputing.com/1011/1011r1.html.) WebObjects is one of the strongest application servers available, and it makes an excellent companion to OS X.

OS X comes preloaded with all the pieces required to use WebObjects right away. The Apache Web server is bundled with OS X (though WebObjects also supports IIS via ISAPI, Netscape via NSAPI, and most other WAI- or CGI-compatible Web servers running on NT 4.0, Solaris 2.6 and HP-UX 10). Apple provides native database access for Informix, Oracle and Sybase, and bundles the Openbase Lite database for prototyping.

WebObjects' EO Modeler, the tool used to map databases, objects and relationships, is extremely well designed. It's one of the better data-modeling products we've used. The IDE contains a variety of coding, debugging and application-monitoring tools designed for programmers. Provided your application is relatively simple, the Direct to Web "super-wizard" also makes it fairly basic to do database-to-Web mapping without writing code.

Apple bundles with OS X the Developer edition of WebObjects, which has a standalone price of $1,499. The number of concurrent users is unrestricted, but database transactions are limited to 25 per minute. This should be sufficient for most small-to-midsize enterprises and for application development in larger shops; heavy-duty users likely will need to upgrade to higher-capacity (100-transactions-per-minute or unlimited) deployment licenses.