I know that BREW has no API to access data in Raw mode.
But perhaps a handset has APIs which meet our requirement.
How can BREW application call its APIs?

Please give me advices and knowledge.

You mean direct call to OEM layer APIs...Not possible. One way is to get those APIs in the form of Brew extension and then use it from app.

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Atul

I will investigate BREW extension now.

Thank you for your Kindness and gentle cooperation.

I dont think Extension is required always. It purely depends upon your requirement.

If you have direct access to the Device API, means you are testing your code in the workspace which includes device API too, then you can call it directly.
Also you can have a simple wrapper function if you want to avoid the headache of writing an extension for calling one device api.