Both the Meter and the APP store data.
The Meter automatically maintains a backup of the most recent 36 days of readings. Even if we are away from the Meter, it will continue to record the temperature and humidity of the surroundings. When the record reaches 36 days, it starts to overwrite the oldest data points.
Once the data is picked up by the APP, it will be stored indefinitely by the app on your mobile device.
Likewise, once the data is picked up by a SwitchBot Hub Plus/Mini (when a Hub Mini/Plus is used in conjunction with the Meter), it will be stored indefinitely in the cloud service of SwitchBot Meter.