Getting consumers to download your app is really hard. Even harder, though, might be getting consumers to use your app for the first time, much less on a regular basis. Fortunately, companies that can tackle this challenge have emerged.

The challenge itself has a lot to do with how dynamics shift as users go from download to usage. Once that consumer has completed the download, your app’s competition changes from other apps in the Store to every other thing your users can do with their phones. That means your app’s competition for usage includes browsing, listening to music, taking and sharing photos and videos, and even texting and placing phone calls.

This blog has focused largely on how to get that elusive download, but today I’ll shine a light on the importance of driving app usage after the download has occurred. These efforts deserve attention, too, because developers need both downloads and usage to make money.

I came across this story in TechCrunch last week, which describes one company that is taking on the usage problem. It’s called Appboy. The young firm and its 30 employees are focused on giving developers tools they need to measure and understand their users. It also provides resources with which to engage them and keep them coming back to an app after they’ve downloaded it.

It may not seem obvious at first glance that developers can engage in direct response marketing to their app users, but they can. If built the right way, apps can deliver push notifications, e.g. a beep or vibration that indicates a breaking news story or weather alert is available in an app, in-app messaging, or via email, presuming the app collects email addresses at registration. Appboy offers to help companies build the right communication program for their users that balances the developer’s incentive to maximize its engagement with the user and the user’s sense of how much and what kind of marketing she is willing to accept.

Efforts to drive user engagement will open up all sorts of new and crucial topics for mobile marketers to consider, including the ideal success metrics to track, what in-app marketing platforms are most effective, the ideal times of day and week to try to reengage an app user, and what sort of creative content will be most effective.

Getting the download is just the first, really hard thing a developer needs to do. Getting a user to come back time and time again is the second. If I had to bet, I’d say that at most companies it’s subordinated to securing the download. It certainly has been subordinated in this blog up to this point.

Companies like Appboy suggest that developers need to rethink the way their marketing resources are deployed. Mobile marketers should take notice, even if they decide Appboy isn’t right for their business.