1# telephony_data.h
2
3
4## Overview
5
6Defines C APIs for cellular data module.
7
8**Library**: libtelephony_data.so
9
10**System capability**: SystemCapability.Telephony.CellularData
11
12**Since**: 13
13
14**Related module**: [Telephony Data](ndk-apis-telephony-data.md)
15
16
17## Summary
18
19
20### Functions
21
22| Name| Description|
23| -------- | -------- |
24| [OH_Telephony_GetDefaultCellularDataSlotId](ndk-apis-telephony-data.md#oh_telephony_getdefaultcellulardataslotid) | Obtains the default SIM card used for mobile data.|
25