General questions:

  1. What does the application do?
  2. How it uses the required permissions?
  3. Is the application free?
  4. Is the source code available?

    5. Device list questions:

  5. Why can't I see my device on the list?
  6. How can I see the advertising data of the device?
  7. Why some rows in the device details have a blue label?
  8. Can I clear the list of devices?
  9. Can I filter the list of devices?
  10. What is the RSSI?
  11. Why the RSSI values are different on two Android devices?
  12. Why the RSSI graph ends few seconds after it has been found?
  13. Can I copy the advertising data to another application?
  14. Can I export the graph to EXCEL or CSV format?

    15. Advertiser questions:

  15. Why the advertiser is not supported?
  16. How can I start advertising?
  17. Why the device name is different then I have set?
  18. Why I can't connect to an advertising Android device?
  19. What's the difference between Advertising data and Scan Response data?
  20. The app does not advertise with data I specified. Why?
  21. The app advertise with old data that I have removed. Why?

    22. Connection questions:

  22. What does autoConnect mean?
  23. How can I bond to the device?
  24. Can I connect to more than one device at once?
  25. Can I save or export the log?
  26. How can I enable all notifications at once?
  27. How can I write any bytes to a characteristic with a custom writer?

    28. Other questions:

  28. What is the DFU?
  29. How to create the DFU Distribution packet (ZIP)?

    Answers:

  1. What does the application do?

    The nRF Connect is an application that lets you scan, discover, and debug your Bluetooth Low Energy devices. It displays the list of advertising devices and allows you to connect to them, and read and write data. You must have a Bluetooth 4.0+ device in order to make use of the application.

  2. How it uses the required permissions?

    The application currently requires the following permissions:

  3. Is the application free?

    Yes. The application is available on Google Play free of charge.

  4. Is the source code available?

    No, the source code is not available. If you would like to suggest some change, report a bug or make a feature request please contact us using the "Send feedback" button in the menu. If you are interested in a sample code, we've released the source code of our other applications (e.g. nRF Toolbox, nRF Blinky) for Android and iOS on GitHub. Please, go to GitHub/NordicSemiconductor for more information.

  5. Why can't I see my device on the list?

    The nRF Connect application scans for all Bluetooth LE devices in the range. Your device may not be visible on the list if at least one of the following statements is true:

  6. How can I see the advertising data of the device?

    Click on the device row to expand it and see the advertising data in an accessible form. Click on the RAW button to see the unformatted raw data. The MORE button shows detailed advertising history.

  7. Why some rows in the device details have blue label?

    Some data in the advertising packet may be parsed in different ways. nRF Connect gives you an option to change the parser assigned to this value by clicking a row with blue label. List of available parsers varies and depends on the value length and format.

  8. Can I clear the list of devices?

    Yes. Use the refresh item from the menu or pull the list of devices down.

  9. Can I filter the list of devices?

    Yes, click the "No filter" on the SCANNER tab to expand a filter view. You may filter devices by the address, name and highest required RSSI. You may also mark a device as favorite by pressing its icon on the left. An orange star indicates that it's favorite and will be shown.

  10. What is the RSSI?

    The RSSI (Received Signal Strength Indication) is a measurement of the power present in a received radio signal. It's usually displayed in dBm (Decibel-milliwatts). Low power devices, like Bluetooth Low Energy devices, are using very week power to transfer data, therefore the usual values of RSSI are between -100dBm (very week signal) to around -20 dBm (strong signal).

  11. Why the RSSI values are different on two Android devices?

    By definition the RSSI value is a measurement of the power present in received radio signal. The signal strength depends on the antennas, device orientation, location, distance from the phone to the target device, humidity etc.

  12. Why the RSSI graph ends few seconds after it has been found?

    On some phones (f.e. Nexus 4 and Nexus 7) the application is being notified only about the first advertising packet received during one scanning. This value is being shown on the graph. After few seconds, when no more packets are received, the graph ends for this device. You may disable continuous scanning in Settings->Scanner. When disabled the application will scan in 1 second periods which will keep the graph going. This option should be enabled if your phone/tablet does not have this issue.

  13. Can I copy the advertising data to another application?

    Yes. Long-press the row you want to copy to go to selection mode. You may select more device while in selection mode by pressing other rows. Click COPY or SHARE icon to copy the devices' data to your application or select the SAVE option to save it in a file. You may also export the advertising data to the nRF Logger application.

  14. Can I export the graph to EXCEL or CSV format?

    Yes. Please, long-press the row you want to copy to go to selection mode. You may select more device while in selection mode by pressing other rows. Press on the SAVE menu and select desired format.

  15. Why the advertiser is not supported?

    The advertiser API is available since Android 5.0 Lollipop. However, not all devices with this system version support it. You may quickly find out which features your devices support in the Device Information page (open it from the navigation menu). Be sure you have the Bluetooth adapter enabled.

  16. How can I start advertising?

    You have to create an advertising packet. It can be done in two ways: a creator (click on the floating red button with +), or by cloning a scanned device (expand its row and click CLONE button). After the packet was created it can be edited using the EDIT button. To start advertising make sure the Bluetooth adapter is enabled and switch the ON/OFF switch on the packet row to ON position.

  17. Why the device name is different then I have set?

    Android API does not allow to advertise with a custom device name. It allows only to add or not to add a phone's name. The phone's name can be set in the top menu. The 'Display name' field is used just to display the packets on the ADVERTISER tab.

  18. Why I can't connect to an advertising Android device?

    Make sure you have set the 'Connectable' switch in the packet editor. A cloned packet, on Android version before 8, by default is set as non-connectable. Since Oreo the flag is copied from the cloned packet.

  19. What's the difference between Advertising data and Scan Response data?

    In Bluetooth 4+ a device, if not connected, continuously advertises with the Advertising data. When a scanner receives it, it may send the Scan request packet to obtain more advertising information. Then, the advertising device sends the Scan response data. Both packets may have up to 31 bytes.

  20. The app does not advertise with data I specified. Why?

    Most probably it's because of an Android bug. Up to now (Android 6.0) only a single Service Data or Manufacturer Data are being advertised in the Advertising Data or the Scan Response data. This means you may have up to 2 of each, a single S-D and M-D in Advertising Data, and another pair in the Scan Response data.

  21. The app advertise with old data that I have removed. Why?

    Just like in the previous question it is an Android bug. If you had set the Scan Response data, and then removed it, some devices (all we used for testing) advertise with the last value, even though the null is passed as Scan Response. Try to reset the Bluetooth or the Android device.

  22. What does autoConnect mean?

    When connected with autoConnect the Android will try to establish connection whenever the device is in range. Please, refer to Android documentation for more information.

  23. How can I bond to the device?

    You may bond to a device in 4 ways:

  24. Can I connect to more than one device at once?

    Yes, simple go back to the SCANNER tab and connect with another device. The maximum number of simultaneous connections depends on the phone/tablet and is usually 6 or more. You may also scan for devices or advertise (supported on newer devices with Android Lollipop or newer) at the same time.

  25. Can I save or export the log?

    Yes. If you have the nRF Logger application installed on your phone/tablet the log session may be saved automatically. See Settings->Logger for more options. If you are not interested in this application you may always save the log to a file, copy it or share it using the menu below be log.

  26. How can I enable all notifications at once?

    When connected open the device menu and select Enable services. You may also read all characteristics at once. Those operations may take some time depending on the interval connection of the device and number of characteristics.

  27. How can I write any bytes to a characteristic with a custom writer?

    nRF Connect has build in parsers and writers for number of characteristics. If you want to disable this feature and use the default dialog uncheck the "Parse known characteristics" option in the menu.

  28. What is the DFU?

    DFU (Device Firmware Update) is a protocol used to transfer an updated version of the application, SoftDevice or a Bootloader on a nRF5x chip Over-the-Air. Please, see the documentation for more details: link.

  29. How to create the DFU Distribution packet (ZIP)?

    The nrf util Python tool is available on GitHub. You may find the init packet documentation here: link.