The concept of situational applications, software written to be "good enough" for a very focused, limited set of requirements, has been around for a long time now. Of late, with the rise of Web 2.0 models of application delivery, the concept has enjoyed a renaissance, driven by vendors and advocates (most prominently, Jonathan Sapir of SilverTree Systems) pointing out the possibilities of SaaS and PaaS solutions to fill this role.

I've pointed out previously that there has traditionally been considerable danger in these "good enough" user-driven applications in that they can lead to data silos in the organization that the CIO will be forced to deal with and de-duplicate at some point in the future, should they prove successful. The concept has been tarred and feathered in IT management circles for so long that it's become something of a trope, an idea that most CIOs discard out of hand.

The way that these applications are being developed and deployed is different, however. The iPhone and Apple's AppStore have revolutionized the specific-purpose application. These new situational apps have a different pedigree than their predecessors. They fit the model of centralized data and security while distributing functionality and control in ways that many earlier generation situational applications did not. This is due in no small part, I believe, to the platform they are being developed for: you would have a tough time building out a full scale payroll system for the iPhone. But putting a front-end on an existing SaaS package? No problem.

Another difference is that, traditionally, situational applications were seen as having been developed either by end-users or at least very close to that level of the organization. It was presumed that no one else would have the incentive to drill down to so specific a need, to devote valuable development time to such specific and relatively trivial requirements. But that view didn't take the economic incentives of the AppStore into consideration. Professional developers, by scratching a very focused itch that users had on a small scale in many different organizations, could attract such compensation as they felt their due in ways that could never happen in a single company. So the quality of the code and interface has been well beyond that which most amateur developers could provide in the past.

It's not just the iPhone that makes this possible, of course. Sapir is quite correct when he notes the potential for PaaS and SaaS powered situational apps, and the web itself has seen an explosion of what Jason Kottke has labeled "Single Serving Sites" that may be even more narrowly focused that the most narrowly focused iPhone application. I think the key to the future of the situational application, though, will be combination of development tools that allow developers to produce them relatively quickly, combined with a platform that allows easy monetization of those efforts, probably across a broad audience. So far, the iPhone seems to be the only thing that has combined those elements in the right proportion, but I don't doubt that we will see more coming.