There is no charge to download the app, but a Verizon Wireless data plan is required and usage may count toward a customer's data allowance.

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In addition to a 30-day overview of users' app data usage, Onavo Count also gives users individual App Profiles, complete with charts that track weekly data usage and gauges that measure individual app's overall mobile data usage.

ENGADGET: Data hungry apps revealed with Onavo Count, free usage tracker for iOS

And with Onavo, iPhone users can now finally understand their apps' data usage by keeping Count!

ENGADGET: Data hungry apps revealed with Onavo Count, free usage tracker for iOS

Wi-Fi usage at public hotspots, home or office does not count toward the monthly wireless data plan usage.

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Not only are Onavo Count's insights unique, but Onavo Count is also the only app data usage monitor that prevents battery drainage by using cloud-based technologies!

ENGADGET: Data hungry apps revealed with Onavo Count, free usage tracker for iOS