Find the break in the signal.

Practical checks for permission, discovery, connection, subscription, and payload issues.

Bluetooth permission is denied

iOS

  1. Open Settings → Privacy & Security → Bluetooth.
  2. Enable access for BLE Developer Console.
  3. Return to the app and retry.

Android

  1. Open Settings → Apps → BLE Developer Console → Permissions.
  2. Allow Nearby Devices or Bluetooth permissions.
  3. On older versions, allow Location permission and enable Location Services.

No devices appear during scanning

  • Confirm the other device is actively advertising
  • Keep devices within one to three metres
  • Restart the scan and the other device’s advertising
  • Toggle Bluetooth and recheck Android permissions
  • Ensure another app is not holding the connection
  • Test with a standard BLE service UUID

Connection fails or drops

  • Move devices closer and reduce 2.4 GHz interference
  • Disconnect the peripheral from other apps
  • Stop scanning before reconnecting
  • Keep both apps foregrounded while diagnosing
  • Disable aggressive Android battery optimization
  • Reduce payload frequency and size

Connected but not ready

The central connected but has not subscribed to the configured characteristic.

  • Enable Notify or Indicate
  • Confirm service and characteristic UUIDs
  • Ensure the central completed service discovery
  • Confirm the central subscribes to updates

Payload sent but not acknowledged

A compatible acknowledgement was not received before timeout. Confirm the receiver remains connected and subscribed, retry with a smaller payload, and verify it implements BLE Console’s acknowledgement format.

Platform-specific checks

iOS Peripheral mode

Use a physical device, keep the app open during initial testing, grant Bluetooth access, and configure Write plus Notify or Indicate.

Android background operation

Disable battery optimization, allow background activity, and check manufacturer-specific battery-management settings.