Is there any iphone app that allows user to retrieve the data through google credentials?

I want to allow the user to access the data of 开发者_Go百科iphone app through the google credentials. Is there any app or source code to implement same on my iphone app.

Please suggest step by step. I tried a lot of times but not succeeded.

please anyone's help will be most appreciated.

Thank you, Madan Mohan.

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Maybe a dead end, but try

http://code.google.com/p/gdata-objectivec-client/

Here is a blog http://johntwang.com/blog/2009/06/08/how-to-use-google-apis-with-iphone-sdk/

Hope it helps

Update: Found this http://googlemac.blogspot.com/2009/03/using-google-apis-in-iphone-app.html