The fitness tracker is designed with a built-in USB plug, so it could be charged without a separate charger. You can charge it by any electronic outlet, such as the charger of your phone, a computer or USB plug.
Please pull off the watch face from the straps and put the built-in USB charging plug (where the metal strips located) into a standard USB port.
When it is charging, the battery symbol will display on the screen for 5 seconds. Press the touch key, and the battery symbol will be displayed again. If nothing appears when you press the touch key, please flip it over and turn the device charging plug in the opposite direction.

Please download 'BIGGERFIVE' app and register a account first. Then open bluetooth and enter the app to add device on Device page, select kid account and click Bracelet to bind watch. After bound, the time will be synced with phone.

When removing watch bands, please note that they need to be slide in a parallel direction, please do not bend them down or up and pull when removing straps. This may be fairly difficult intially, but it become looser later. You just have to pull hard. see more

The compatibility of the BIGGERFIVE is Android 6.0 above or IOS 9.0 above, Bluetooth 4.2. (not for PC, iPad, Tablet or windows system). BIGGERFIVE app may not work with US version Samsung Galaxy J series mobile phones (e.g. Galaxy J3，J7).

Usually, the battery will last 3-7 days, but the standby time will be different under different conditions. For example, it will be reduced if you often use Sport Mode or tap the screen from time to time. If you want the device to run longer, please go to the APP page to turn off a few of the functions that you seldom use

Please note that the fitness tracker will reset under the following situations:
1) The watch steps will reset when a new day begins;
2) The bracelet will be off automatically if there is no power, and it will be on once you put it to charge, then the time will reset. So you need to connect the watch with your phone again to sync the time.

It has to be connected with a smart phone by the application "BIGGERFIVE" before initial use. Because the date and time of the fitness tracker can only changed by connecting with a smart phone. After connected with a smart phone once, it can used alone to check the steps, calories, heart rate, moving distance, and active minutes. The activity data can be showed on the display of the fitness tracker. But for the information of sleep quality, it only records in the application.

Yes, it is waterproof. It supports sweat-proof, rain-proof and splashed water proof etc. It is no problem to wash you hands or doing some washing/cooking by wearing it. But it can not be kept under the water for a long time, so we would not recommend you to swim with it. And for any wearable devices, it will be better for its using life to keep it dry and clean.