The concept of apps on our mobile devices is nothing new and dates back years before the iPhone launched what would later be referred to as a gold rush for app developers.  The growth that’s been seen on the iPhone is unlike anything the mobile world has seen and it has clearly set a precedent.   If you’re looking to become a major competitor in the mobile device market, you had better back it up with a significantly sized app catalog.

As always, the iPhone’s been talking up the App Store numbers since they set the trend back in 2008 with the iPhone 3G.  Since it’s unveiling back in March of 2008, the number of available apps in the store has climbed to a dizzying 170,000.  Every advertisement Apple pushes centers around its app catalog with the often-mocked iphoneapps“There’s an app for that” slogan.  One point Apple was sure to make during the iPad announcement was that the 9.7” device would have access to 99% of those 100,000+ applications.  Without access to those apps, the weekend iPad sales numbers that have been reported would likely be a bit deflated.

While the Nexus One may not have seen extraordinary device sales since it’s debut on T-Mobile back in early January, Google’s reaffirming their success through Android Marketplace’s application catalog growth.  Google has seen their app numbers double in four months while application sales have tripled in the same period.  Couple those numbers with 60,000 Android handsets shipped each day and it’s easy to see how Android will soon trump its competitors in marketshare sooner than anyone might have expected.  As the Marketplace continues to grow, expect the flow of Android phones to catch some impressive momentum.

Palm was the subject of some app store mockery back when the iPhone 3GS was announced mid-2009.  Although their marketshare has remained in the single digits, they’ve grown their library to 1,000 earlier this year.  They too have begun their own app marketing push as Palm.com now displays the WebOS apps front and center.  Thankfully, Palm’s got a new outlook on app development, bringing app developers to the platform with their recently released PDK that allows for more full-featured application creation.

When customers head to the store to pick out their latest smartphone, you can bet they’re going to be looking for a store to download applications they see their friends using.  Perhaps David Pogue’s motion to move past the term ‘smartphone’ and instead onto ‘app phone’ at least has a foundation.  What do you think?  Are apps really what sell a phone?  Is it more the brand or the UI?  Share some thoughts in the comments.