Google will block an Apple iPhone application that harnesses its Google Talk chat program to provide a free text-message service after too many users flocked to download it.

The Infinite SMS app, which cost $0.99 and let users send unlimited text messages from an iPod or iPhone, quickly became one of the 10 most-downloaded apps in the iPhone Store after its release last month, developer Inner Fence said in a statement on its website.

But the company stopped sales of the app on Monday after Google notified it that the program would be blocked, Inner Fence said.

Free iPhone SMS"Google has claimed no grievance with Infinite SMS other than its success. Their given reason for the block isn’t abuse or wrongdoing; it’s that we brought too many users (and thus too much cost) to an experimental service," Inner Fence said.

The company said it built the application using an open protocol made available by Google for just such a purpose. "We never could have guessed that the two of us would write an app too big for Google," the company's founders said.

Google said it would continue to offer free SMS through Google Talk, but it will block Infinite SMS and other non-Google clients that use the service to deliver text messages starting today.

"Infinite SMS is a third party app that has been using Google technology to provide free SMS to users, while we were paying for the cost of the text messages," a Google spokesman said.

Infinite SMS was popular with iPod touch users who wanted to send text messages as if they had iPhones, according to Inner Fence.

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