The working time of the device depends on many factors, for example:
Network conditions include network signal strength, level of urbanization, user’s movement in the field, network operation mode (GSM / UMTS / LTE)
Brightness and time of activity of the display backlight
The method and intensity of use, including duration and number of connections (voice, video) / SMS / MMS, frequency of using such functions as eg camera / camcorder, MP3 player, video player, built-in TV, radio, voice recorder, calendar, calculator
Additional applications installed, e.g. some games that can work in the background even after they are closed.
The amount of data sent, e.g. via the application’s web browser
The demand for computing power of the processor (main, graphic) by used applications, e.g. installed games and applications
Time of WiFi, Bluetooth, GPS activity, data transmission
The above factors affect the operation time of each device. The working time given by the cataloger determines the maximum possible standby time in laboratory conditions.