Yes, we take some extra time and check all the functions and the hardware. This includes camera, GPS, sensors, display, charging tests as well as an assessment of external defects. If a new firmware is available for the device, we will update it. In case of errors, we will change it before shipment and a new fully functional device will be sent to the customer. In this way, we guarantee that our customers receive only faultless devices. If you do not agree to these tests, please let us know when ordering. Please also note that in some cases - but in the rarest cases - images may remain on the device due to the tests.