Location based playback system control

A method comprising:

• a mobile device displaying, on a touch-screen graphical display within a first control interface of a controller application, a control to select among playback devices of a media playback system;
• the mobile device receiving, via the first control interface on the touch-screen graphical display, touch-input data indicating a selection of a first playback device for playback of audio content;
• in response to the touch-input data indicating the selection of the first playback device, the mobile device displaying, on the touch-screen graphical display, a second control interface of
• the controller application, the second control interface including one or more playback controls to control playback by the first playback device;
• the mobile device receiving, via the second control interface on the touch-screen graphical display, input data indicating a command to play back the audio content;
• the mobile device determining whether the mobile device is in proximity to the first playback device;
• if the mobile device determines that the mobile device is within a given proximity to the first playback device, the mobile device transmitting, via a network interface, one or more commands to instruct the first playback device to play back the audio content;
• and
• if the mobile device determines that the mobile device is outside the proximity to the first playback device, the mobile device displaying, on the touch-screen graphical display, a prompt indicating that the mobile device is the outside the given proximity to the first playback device and a selectable control that, when selected, transmits the one or more commands to instruct the first playback device to play back the audio content.

A mobile device comprising:

• a network interface;
• a touch-screen graphical display;
• one or more processors;
• data storage having stored therein instructions executable by the one or more processors to cause the mobile device to perform a method comprising:
• displaying, on the touch-screen graphical display within a first control interface of a controller application, a control to select among playback devices of a media playback system;
• receiving, via the first control interface on the touch-screen graphical display, touch-input data indicating a selection of a first playback device for playback of audio content;
• in response to the touch-input data indicating the selection of the first playback device, displaying, on the touch-screen graphical display, a second control interface of the controller application, the second control interface including one or more playback controls to control playback by the first playback device;
• receiving, via the second control interface on the touch-screen graphical display, input data indicating a command to play back the audio content;
• determining whether the mobile device is in proximity to the first playback device;
• if the mobile device determines that the mobile device is within a given proximity to the first playback device, transmitting, via the network interface, one or more commands to instruct the first playback device to play back the audio content;
• and
• if the mobile device determines that the mobile device is outside the proximity to the first playback device, displaying, on the touch-screen graphical display, a prompt indicating that the mobile device is the outside the given proximity to the first playback device and a selectable control that, when selected, transmits the one or more commands to instruct the first playback device to play back the audio content.