That number could swell if PayPal strikes a deal with Google to support mobile application purchases in its Android Market.

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Updated versions of each app, incorporating the SYNC application programming interface (API), will be available through Android Market and BlackBerry App World for customers to download.

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Application developers have embraced Google's two-year-old Android Market because they want alternatives to Apple's App Store.

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The Gogobeans mobile application, which will officially launch April 15 in the Apple App Store and Google Android Market, is also suited to mobile payments.

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