Simplify the following text for a Grade 5 native English-speaking person.
Original: Mobile phones are also commonly used to collect location data . While the phone is turned on , the geographical location of a mobile phone can be determined easily ( whether it is being used or not ) , using a technique known multilateration to calculate the differences in time for a signal to travel from the cell phone to each of several cell towers near the owner of the phone .
Simplified: When a mobile phone is switched on , it connects to the nearest mobile phone base station .