AdMob surveyed more than 1,000 iPhone, iPod touch and Android users and here's what they found:
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• Android and iPhone users download approximately 10 new apps a month, while iPod touch owners download an average of 18 per month
• More than 90 percent of Android and iPhone OS users browse and search for apps directly on their mobile device instead of their computer
• Upgrading from the lite version was the top reason given when users were asked what drives them to purchase a paid app
• iPhone and iPod touch users are twice as likely to purchase paid apps than Android users.
• Users who regularly download paid apps spend approximately $9 on an average of five paid downloads per month
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The stat showing 90% of users look for apps directly from their mobile device is significant because it's that use case that can increase adoption and stimulate sales for the non-mobile app.
A few examples are DropBox, Evernote, Remember The Milk and Box.net. Without my exposure to the iPhone version, chances are I wouldn't have upgraded to the full blown version. Increasingly, we all want to move back and forth between our desktop and mobile environments.
With that comes the desire to have things in sync and generally accessible with the same interfaces we're used to. As you develop your service or product, think about how those two environments need to complement each other. A consistent user experience, and one that extends to mobile, will certainly increase your chances to build brand and generate some revenue.