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Figure 2. Using a laptop on the corner of a beverage trolley [ 4].

the present-day multidevice environment implies having additional tasks of transferring operation and data across devices and places. For this, users must be conscious of the various technological “seams” working counter to their goals, such as discontinuities in connectivity or electricity.

The workers exhibited intricate knowledge of the supportive and constraining factors particularly in local and frequently visited places. For other kinds of trips they had to choose strategies that addressed uncertainty over possible seams.

Some workers used server backups that they knew they could access in a place with a wireless connection. When anticipation was not possible or desired due to cognitive cost, users disciplined themselves to take backups of important files on their smartphone, for example, when going on a longer trip. If, for some reason, the laptop

was not available, a product presentation would then be available from the smartphone. Such “just in case” backup devices were taken along also on shorter trips within the office, where there was a possibility of encountering an important colleague.

The workers also employed a variety of strategies to share documents between their devices. Each device provides different affordances to access information, and users were sensitive to those. Some users did “data mirroring,” copying files to the smartphone for read only. Two-way synchronization, updating file versions on each device after each update, was the most laborsome strategy as it required its adopter to discipline herself to do it, for example, in the mornings. When upcoming situations were predictable, a worker could get by with opportunistic synchronization of a single device.