Abstract
Evaluating mobile technologies “in the real world” is hard. It is challenging to capture key situations of use, hard to apply established techniques such as observation and “thinking aloud,” and it is complicated to collect data of an acceptable quality. In response to these challenges, a “field laboratory” has been developed for evaluating mobile technologies in situ. Facilitating high-quality data collection as well as unobstructed user interaction, the field laboratory allows a small wireless camera to be attached to a mobile device, capturing a close-up image of the screen and buttons. This chapter describes the iterative development of the field laboratory over 4 years of evaluating several mobile systems in field settings. It leads to a description of the current setup and how it is used, and explains the rationales for key decisions on technology and form factors made throughout its development.
Key Terms in this Chapter
Camera-Clamp: A tiny camera that can be clipped on to a mobile device such as a PDA or a mobile phone. Camera-clamps can be either cabled or wireless. The latter require a battery supply and a video receiver.
Quad Display Unit: A video unit that merges four different video signals into one composite signal. All four video images are rescaled and thus lose a bit of quality in the process.
Close-Up View: A video recording of the screen and buttons on a mobile device such as a PDA or mobile phone, during an evaluation of use or usability; usually captured with a mobile devices camera attached to the device.
Lapel Microphone: A small microphone that can be clipped on to a person’s collar or revere. The microphone is usually connected to a small transmitter that can be carried in a pocket or clipped on to the belt.
Picture-in-Picture Unit: A video unit that inserts a video image over a part of another one. The inserted video image is rescaled and thus loses a bit of quality in the process.
Third Person View: A video recording of the user(s) of a mobile device and their immediate surroundings during an evaluation of use or usability from the perspective of a third person observing from a distance.
AV Hard Disk Recorder: A video unit that records an external video and audio source directly onto a hard disk in a digital format that can be played back on a computer. The video recording is typically compressed when it is recorded resulting in manageable file sizes.
Field Laboratory: A configuration of laboratory equipment, such as video and audio recording devices, put together so that it can be taken into to field for data collection about the use and usability of mobile technologies in situ.