People will download more than 182 billion mobile apps in 2015, according to a new report from IDC.

That's up from 10.7 billion apps downloaded in 2010, according to Scott Ellison, the author of the report.

Both Apple and Google are each seeing 1 billion apps downloaded per month and Apple has already had 14 billion cumulative apps downloaded since the App Store opened, he said.

IDC's expectations dwarf those of ABI Research, which published a report in April saying that it expects a total of 44 billion cumulative app downloads worldwide by 2016. ABI could not explain how the figure was calculated; the analyst who wrote the report is based in Singapore and was unavailable to comment.

However, more interesting than the volume of app downloads will be the way that app developers monetize the apps in the future, IDC's Ellison said.

Currently, developers rely almost entirely on app purchases for their source of monetization. But using in-app purchasing is fast becoming their method for generating revenue, he said. App developers are emulating creators of mobile games who have long used in-game sales of additional levels, features and functions for revenue.

He points to a survey done by IDC and Appcelerator in the first quarter in which developers reported dramatically increased plans to use in-app purchasing, mobile advertising and mobile commerce in their products.

The shift toward monetizing through in-app purchases will require app developers to think differently about their apps in terms of how they incorporate in-app purchasing, he said.

In its report, ABI points to changes that could further encourage app downloading. It points to a rumor that Apple has made changes to the App Store so that it considers qualitative information such as reviews in addition to download statistics when ranking apps. That means that apps that sound better than they really are won't continue to take top spots in the ranking, ABI said. Those apps sometimes remain at the top as people download them and then discover they aren't useful.