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S60 devices have been categorized into three classes based upon the GPRS connectivity during active GSM call.

Contents 1 Class A 2 Class B 3 Class C 4 NOTE:

Class A

Can be connected to GPRS service and GSM service (voice, SMS), using both at the same time. Such devices available today (N73/80/91/93, E60/61/70 etc).

Class B

Can be connected to GPRS service and GSM service (voice, SMS), but using only one or the other at a given time. During GSM service (voice call or SMS), GPRS service is suspended, and then resumed automatically after the GSM service (voice call or SMS) has concluded. Most GPRS mobile devices are Class B(N70,N90,6680 etc).

Class C

Are connected to either GPRS service or GSM service (voice, SMS). Must be switched manually between service.

NOTE:

There is no direct API to query about the supported GPRS class in a device.Most of Nokia 3G (WCDMA) phone models support GPRS class A. The feature discovery API can be used to detect if a phone model supports WCDMA stack. Here is some snippet code:

TBool isSupported = CFeatureDiscovery::IsFeatureSupportedL(KFeatureIdProtocolWcdma);
if (isSupported)
      // activate the service

For more information about feature discovery, refer the API reference in the SDK.