The life cycle of a new hot web application platform looks something like this: 1. the platform launches amid a lot of hype, 2. advertisers and speculators swoop in, 3. the platform is flooded with applications, most of which are silly or useless, 4. as a result the good applications get obscured, and people lose interest because discovery becomes such a big problem.

The flood of applications that inevitably follows the launch of a hot new web app platform leads to what we’ve termed app fatigue. Once the number of apps hits a saturation point, people start feeling overwhelmed by the sheer number of applications they’re presented with in the given app store or application gallery. That in turn leads to increased selectivity and the potential for people to dismiss the entire platform as just a collection of trivial time wasters.

This is what happened to Facebook. When the platform launched, there was a huge amount of buzz around the potential for advertisers and app developers. Subsequently, a huge number of applications were created on the platform and users were faced with a rising tide of apps that demanded their attention. End result: app fatigue. We started seeing app fatigue set in less than a year after the platform’s launch when there were just over 15,000 total applications — there are now over 53,000 apps on the Facebook platform, according to Adomonics.

Facebook has done some things to try to address the app fatigue and discovery issues — via design tweaks and rules on how apps can spread, but nothing has so far worked very well. Eventually, people who were once heavily invested in the success of the Facebook platform actually declared it dead.

The same thing looks like it might be happening with the much vaunted iPhone platform.

In November we reported that the iPhone platform had crossed the 10,000 app mark, but we wondered how many are really worth your time.

“The comparison with the Facebook platform is unavoidable,” we wrote in November. “Though there are clearly many differences (iPhone developers can charge for apps, for example, and iPhone users, since they paid for the phone and monthly service, are likely more willing on the whole to pay for apps), there are also similarities, so the comparison is warranted. As more and more developers flock to these platforms to try to make a quick buck, the noise level inevitably rises. We’re seeing it on Facebook, where the number of apps continues to grow steadily, but user engagement has leveled off.” (Note: there are about 5,000 new apps on the Facebook platform since November 30 when we ran that post, according to Adomonics numbers.)

The number one paid app right now in the iTunes App Store is iFart Mobile (iTunes), an application that simulates farting noises. Clearly, there must be some market for this $0.99 app, but it is also the type of silly/useless application that pushes down the good stuff while raising the noise level and might ultimately lead the iPhone application platform down the same path that Facebook’s has taken.

A recent survey from Compete found that 45% of iPhone owners had added 11 or more apps from the App Store. Compete concluded then (November), that “part of the application appeal may be how easy it is to find and add them to the iPhone.” By controlling distribution of applications, Apple has made it simpler for users to find and install apps on their phone platform. It’s a model that others are starting to emulate — there are now app stores available or coming from Microsoft, Blackberry, Google/Android, Nokia, Yahoo!, O2, and Palm.

The flood of applications is already becoming a problem, though. “With such a wide variety of platforms, stores, and applications, discovery is actually becoming the big problem these days,” writes Mobile Advertising News.

The big issue for these platforms isn’t so much how many apps are worth your time — with tens of thousands of applications there are undoubtedly a large number of good ones — but rather, how to weed out worthwhile apps from the fluff. With such a high level of noise, the signal is being lost and fatigue is setting in, causing users to lose interest.

We’re not sure what the solution is, but clearly app fatigue is already visible on the horizon for iPhone users, and it’s already plaguing Facebook users. We predicted in October that fluff apps would start to fade away on the Facebook platform as developers determined that the opportunity to make a quick buck had passed, and eventually useful applications would rise up in their place to form a smaller, but more valuable application ecosystem. It was a nice theory, but so far nothing has happened to make us think that will actually come to pass.

Perhaps, though, that’s just the necessary evolution of any new web app platform — launch, hype, land grab, overload, fatigue, fall off … then, rebirth? We’ll see.

Let us know your thoughts in the comments. How many apps have you installed on social networks or on your smartphone? With the sheer number of apps available are your starting to feel overloaded? Are you starting to notice discovery becoming a problem as noise levels rise?