HID keyboard drains iPhone battery quickly

[Jeff]

I am connecting my development device acting as a BLE keyboard using HID over GATT and it seems to be draining the phone battery very quickly. Every 7 seconds I would get a pair of HID Suspend/Exit Suspend commands from the phone even when the phone screen is off and the keyboard is not sending any data. If I just connect using ANCS with my device I don't see the same power drain on the phone even when using the same BLE connection parameters. I saw this problem in iOS7 and it still continues in iOS8. Does anyone else see this issue? I cannot find any BLE keyboard products on the market to compare to.

ios8-hid.csv The attachment has the HID activity when the phone is idle. Handle 15 is the HID control point: developer.bluetooth.org/.../CharacteristicViewer.aspx

This is the frame data for the HID suspend/exit suspend commands. Frame 8,400: Len=27 ATT: Signature Present: No PDU Type is Command: Yes Opcode: Write Command Attribute Handle: 15 Unknown Attribute Data: 0x00

Frame 8,485: Len=27 ATT: Signature Present: No PDU Type is Command: Yes Opcode: Write Command Attribute Handle: 15 Unknown Attribute Data: 0x01

[Jeff]

Thank you for the reply. I checked the power consumption of the local device and it is not draining noticeably more power in the keyboard case. The power drain is on the phone side presumably from waking up to send the Suspend/Exit Suspend commands continuously. I was hoping someone can confirm this problem with their phone or with a BLE keyboard with a different chip so I can be sure it is an iOS problem.