Jeff Axup

Usability of a mobile, group communication prototype while rendezvousing

Mobile phones are increasingly being used collaboratively by social networks of users in spite of the fact that they are primarily designed to support single users and one-to-one communication. It is not well understood how services such as group SMS, SMS-based discussion lists and mobile instant messaging (IM) will be used by mobile groups in natural settings. Studying specific instances of common styles of in situ, group interaction may provide a way to see behavior patterns and typical interaction problems. We conducted a study of a mobile, group communication probe used during a rendezvousing activity in an urban environment. Usability problems relating to group usage, phone interface design and context were identified. Several major issues included: multitasking during message composition and reading; speed of text entry; excessive demand on visual attention; and ambiguity of intended recipients. We suggest that existing mobile device designs are overly-focused on individual users to the detriment of usability for mobile groups of users. We provide recommendations for the design of future mobile, group interfaces, used in similar situations to those explored here

The territory is the map: designing navigational aids

It has been shown that people encounter difficulties in using representations and devices designed to assist navigating unfamiliar terrain. Literature review and self-reported visual and textual data from field experiments are presented. This suggests usability may be limited by assumptions about landmarks implicit in designing representations. Firstly, memorable landmarks are emphasized but route following in situ requires recognizable landmarks. Secondly, little emphasis is placed on differences between landmarks contributing to higher-level concepts related to wayfinding and those directly provoking actions in the environment. Studies analyse landmarks in SMS during collaborative wayfinding to an unfamiliar rendezvous and in images to communicate routes in unfamiliar terrain. Findings illustrate usability benefits for navigation aids. This includes helping users to align a landmarks illustration to their individual perspective in the environment. It also includes identifying landmark salience for shared use by people navigating in dispersed groups to dynamically-negotiated rendezvous.

The territory is the map: exploring the use of landmarks in situ to inform mobile guide design

People have difficulties interacting with external representations designed to guide navigating physical environments. We derive theory to inform design by probing users’ experience and use of their “internal” representations in a temporally evolving wayfinding activity in situ. Interactions with environmental landmarks are explored by analyzing spatial concepts in SMSs used by a group collaborating to wayfind to an unfamiliar rendezvous. Results show differences between landmarks provoking actions and contributing to abstract concepts; and, effects of direct or induced perspective in situ. Design recommendations account for orientation dependence and use of ambiguity in user-world-representation mappings. These include tactics to enable users’ to induce perspectives appropriately: with accuracy for recognising landmarks along routes and agility to situate landmark use in naturally evolving wayfinding goals.