A Systematic Assessment of Smartphone Usage Gaps

Abstract

Researchers who analyse smartphone usage logs often make the assumption that users who lock and unlock their phone for brief periods of time (e.g., less than a minute) are continuing the same "session" of interaction. However, this assumption is not empirically validated, and in fact different studies apply different arbitrary thresholds in their analysis. To validate this assumption, we conducted a field study where we collected user-labelled activity data through ESM and sensor logging. Our results indicate that for the majority of instances where users return to their smartphone, i.e., unlock their device, they in fact begin a new session as opposed to continuing a previous one. Our findings suggest that the commonly used approach of ignoring brief standby periods is not reliable, but optimisation is possible. We therefore propose various metrics related to usage sessions and evaluate various machine learning approaches to classify gaps in usage.

Quantifying Sources and Types of Smartwatch Usage Sessions

“…Finally, following the recommendations by Van Berkel et al [35] and Soikkeli et al [34], we verify the existence of continuous sessions consisting of multiple individual sessions within a certain time threshold (T = 45 seconds, as per [35]). This may represent cases where a user quickly and repeatedly uses their smartwatch, with short breaks in between, to complete a larger objective.…”

“…Smartphone usage is typically short, with Yan et al [41] finding that 50% of mobile phone engagement lasts less than 30 seconds. Van Berkel et al [35] distinguish between continued and new usage sessions. Their results show that for the majority of cases in which people unlock their phone, they intend to start a new objective as opposed to continuing a previous one.…”

“…We argue that removing the entries over this threshold discards sessions where the user was not aware of the device's screen being on, or sessions where the user did not interact with the device regardless of the screen being on. Additionally, the sessions analysed by past literature (for smartphones) report continuous usage sessions, consisting of several individual sessions, tend to not exceed five minutes on average [34,35].…”

“…From four previously published studies [10,14,35,37], we aggregate a dataset of 347,576 smartphone screen entries, from 445 unique users between February 2014 and May 2016, which we then transform into 120277 unique usage sessions. Each session has an associated session length (M = 229.34 seconds), and the daily session count (M = 60.08) for that user on that particular day.…”

Investigating how users engage with a pedometer app

“…While well-designed user studies and surveys reveal specific user behaviours, analysis of app-level interaction logs extracts usage patterns in larger user populations. Many researchers have explored how people use their smartphones [2][3][4][5][6]. Further, many studies collect users interactions with specific mobile apps to perform different user studies and app evaluations [7][8][9][10].…”