The device stores up to 200 readings, however, you are only able to view the history by pairing your device to the app. You can use the Bluetooth option on the device and sync to the Gojji app to view the history or manually keep a log in a notebook for your reference. 

Do not use the ifora app because if you accidentally pair to the ifora app, and then disconnect to use the Gojji app the readings that synced cannot be resynced to the Gojji app resulting in some readings being in 2 different systems.