Dear user, we are sorry for your inconvenience. Our App supports the use of multiple mobile phones and multiple platforms to log in to one account at the same time. Therefore, all device data under the account will be uploaded to the cloud and synchronized to all phones logged in to the account (whatever iOS or Android). If you encounter a situation where the timing or countdown cannot be synchronized, it is possible that you are using a Bluetooth device and you have not connected the Bluetooth device to the Bluetooth gateway.