A system comprising a supermarket trolley and a portable electronic device, said supermarket trolley comprising a basket with a handle bar and at least three wheels on its bottom side, a security chain and a deposit lock for connecting said supermarket trolley with another supermarket trolley of the same type, said supermarket trolley being provided with a docking station for said portable electronic device, said docking station comprising a retainer for said device, a voltage source and means for transmitting energy from the voltage source to said device, wherein a) said docking station comprises a detector for detecting the insertion of said portable electronic device into said retainer and/or the connection of said device with said energy transmission means; b) said deposit lock comprises an electromagnetic locking mechanism which is electronically connected to said detector of said docking station; c) said detector of said docking station is capable of transmitting an electric or electromagnetic signal to said electromagnetic locking mechanism of said deposit lock when detecting the insertion of said portable electronic device into said retainer and/or the connection of said device with said energy transmission means; d) said electromagnetic locking mechanism of said deposit lock comprises a receiver suitable for receiving said signal, said receiver being capable of triggering the unlocking of said security chain after having received said signal; e) said portable electronic device is a mobile phone or a tablet PC comprising a rechargeable battery which is rechargeable by transmitting energy from said voltage source via said energy transmission means; and f) said docking station comprises an integrated data storage and/or a receiver for receiving data from an external data source, thus being capable of transmitting data to said portable electronic device which has been inserted into said docking station. a) said docking station comprises a detector for detecting the insertion of said portable electronic device into said retainer and/or the connection of said device with said energy transmission means; b) said deposit lock comprises an electromagnetic locking mechanism which is electronically connected to said detector of said docking station; c) said detector of said docking station is capable of transmitting an electric or electromagnetic signal to said electromagnetic locking mechanism of said deposit lock when detecting the insertion of said portable electronic device into said retainer and/or the connection of said device with said energy transmission means; d) said electromagnetic locking mechanism of said deposit lock comprises a receiver suitable for receiving said signal, said receiver being capable of triggering the unlocking of said security chain after having received said signal; e) said portable electronic device is a mobile phone or a tablet PC comprising a rechargeable battery which is rechargeable by transmitting energy from said voltage source via said energy transmission means; and f) said docking station comprises an integrated data storage and/or a receiver for receiving data from an external data source, thus being capable of transmitting data to said portable electronic device which has been inserted into said docking station.