With the launch of the Apple OS App Store, digital software distribution has hit the desktop in force to the delight of users. The Apple OS App Store recorded one million software downloads on its first day in users’ hands. 50% of new Evernote users come from the OS App Store.

While some of the application sold on the Apple OS App store are digital forms of boxed software, like Apple’s Aperture, many of the most successful apps are mobile apps – games or utilities developed with iOS in mind. In other words, these mobile application developers view the desktop app store as another viable distribution channel. 

Distribution is one of those magic keys to success. Mobile developers have four self-service distribution channels available to them: the mobile app store (the iTunes store), the desktop app store (the App Store), in-app advertising (TapJoy, AdMob) and the web app stores (Android market, GetJar). The costs to acquire users in each channel vary over time and across categories.

As a result of this choice in channels, application developers are presented a new opportunity: they may arbitrage app installs across distribution channels, acquiring users from the least expensive sources first. Arbitraging channels is old news on the web, but relatively new in mobile app distribution. 

In addition to lower customer acquisition costs, cross platform use is the best leading indicator of a user’s proclivity to convert to paid. In some cases I have seen, up to 40% of users who use an app both on the PC and the mobile phone convert to paid.

Experiment with distribution channels. Drive cross platform usage. The investment will reward you with more users, larger revenues per user and lower costs of acquisition.