Article ID : 00202006 / Last Modified : 22/10/2021Print

How to pair the FES Watch U with your smartphone

    This page introduces connection information about FES watch U with a smartphone.
    Please select your topic:

    Basic Information

    Can the watch be used without a smartphone?
    Without a smartphone, the watch can only be used to display the time, change the pattern, and set the time. To use every function (e.g. adding patterns), a connection with a smartphone is required.

    Can the watch be used by multiple smartphones?
    The watch can only register a single smartphone.
    You need to reset the watch before registering another smartphone.

    Does the watch have the functions of a smartwatch?
    The watch does not have smartwatch functions such as lifelogging, tracking or displaying notifications.

    Set up & changing smartphone

    If you change to another smartphone, the watch needs to be initialized, returning it to its default setting.

    After initialisation, connect the smartphone and the watch using the "FES Closet" app to use functions such as sending patterns.

    1. Install the "FES Closet" app from either the App Store or Google Play on the new smartphone.
    2. Launch the "FES Closet" app.
      When the following screen appears, follow the instructions on the screen to connect your smartphone and the watch.
      • Turn on the Bluetooth function of the smartphone.
      • If your smartphone is Android 6.0 or later, allow the “FES Closet” app to access the location information on the smartphone.
    3. Initialize the watch.
      • Tap (Settings) in the top right corner of the CLOSET screen.
      • Tap Watch Settings.
      • Tap Initialize Watch.
      • Tap Initialize Watch on the INITIALIZE WATCH screen.
      • Tap OK on the confirmation screen.

        The following display appears on the watch, and the countdown screen appears on the “FES Closet” app.
      • Press the button on the watch for more than 2 seconds and within 10 seconds after the previous step
    4. Initialization starts and will be completed when the following display disappears.
      (This takes about 30 seconds to 1 minute.)
    5. Connect the watch to your smartphone.


    The content is not displayed correctly on the supported Android device
    If you are using Android 5 or 6, make sure that the Android System WebView app is the latest version. If you are using Android 7 or up, make sure that the Chrome browser is updated to the newest version.


    “FES watch U” cannot be connected to a smartphone

    1. Make sure that your smartphone and the OS support the "FES Closet" app.
      For information on supported OSes and smartphone models, refer to the following article:
      Questions regarding OS information for FES Watch U
    2. Make sure that the Bluetooth function of your smartphone is turned on.
      NOTE: If your smartphone is Android 6.0 or later version, allow the “FES Closet” app to access the location information on the smartphone. For Android 6.0 or later, you need to activate the location information services to detect devices via the Bluetooth function.
      For iOS, the app does not require the location information services to be activated due to iOS specifications.
    3. Check if the (Bluetooth) connection icon is displayed on the watch.
      If the icon is not being displayed, press and hold the button on the watch for at least two seconds.
    4. Check the remaining battery level of the watch.
      You can display the battery icon that indicates the remaining battery level by pressing and holding the button on the watch for at least two seconds.
      A: Full
      B: Empty

      When the battery is almost empty, the empty battery icon automatically appears even if you do not press the button. Please charge the watch accordingly.

      After checking the remaining charge, press the button for more than 2 seconds to turn off the battery icon.
      NOTE: If the battery is used up, it will take 2.5 hours to complete charging.
    5. Take the watch off your wrist and bring the antenna of the watch closer to your smartphone to make the connection more stable.
    6. If the issue doesn't resolve itself after following the steps above, restart the watch by pressing and holding the button on the watch for at least 20 seconds.
      NOTE: You will need to reset the current time after restarting the watch.



    The display does not change even when I operate the button

    If the screen doesn’t change, even when you press and hold down the button, check the remaining battery level. Note that if the watch is used outside of the operating temperature range, it may stop working. If the remaining battery level is sufficient, try initializing the watch:

    1. Press and hold down the button for 20 seconds.
    2. Release the button after the whole screen flashes.
    3. You will be prompted to set the time. Set the time. Afterwards, the watch will initialise.


    When the pattern is changed, an afterimage remains on the display

    An afterimage may appear due to the characteristics of the electronic paper. This occurrence is normal.


    Black and white are reversed while the time is displayed.

    Due to the characteristics of the electronic paper, black and white are reversed to display a distinct image when time advances.