Some demonstrative embodiments include apparatuses, systems and/or methods of estimating a location of a mobile device. For example, an apparatus may include a controller to control a mobile device to transmit a first message to a wireless communication station (STA) and to receive a first acknowledgement (ACK) message from the STA in response to the first message, when the mobile device is at a first location, wherein the controller to control the mobile device to transmit a second message to the STA and to receive a second ACK message from the STA in response to the second message, when the mobile device is at a second location, wherein the controller is to determine a distance difference between a first distance and a second distance based on a first round trip time and a second round trip time, the first distance being between the first location and the STA, the second distance being between the second location and the STA, wherein the first round trip time includes a round trip time of the first message and first ACK, and the second round trip time includes a round trip time of the second message and second ACK.