GOLiFE Fit Smart Scale is a Bluetooth smart scale with Bluetooth data transfer interfaces for connection with mobile phone APP. GFSSL-US has four buttons on the panel for four users to store personal data each person can store up to 50 data; and one key on the bottom for no saving. You can use cell phone transmit height age sex display settings and the unit set to GFSSL-US; Users can set individual privacy through the phone If you would like to keep your personal body weight private there is an option to do so within the APP; this will prevent your weight from showing up on the scale when synced to your mobile device and the APP.