“…System 2 control is driven by goals, intentions, and rules held in conscious working memory [14,124]. From these central representations, signals are sent to cognitive systems that AppDetox, an Android app which let users voluntarily create rules intended to keep them from certain apps None Collins et al 2014 [37] RescueTime, a commercial Windows/Mac application which provides visualisations of how much time is spent in different applications Cognitive Load theory [26] Lee et al 2014 [100] SAMS, an Android app for tracking smartphone usage and setting time limits for app use Relapse prevention model [70,198], clinical guidelines for internet addiction [205] Ko et al 2015 [94] NUGU, a smartphone app which let users set goals for limiting usage, then share performance with friends and receive encouragement Social Cognitive Theory [15] Andone et al 2016 [9] Menthal, a smartphone app displaying the 'MScore', a single number summarising overall phone usage, as well as a series of main usage measures None Hiniker et al 2016 [78] MyTime, an Android app showing time spent in apps (and whether a daily limit was hit) plus a daily prompt asking what the user wished to achieve None Kim et al 2016 [90] TimeAware, an ambient Windows and Mac widget which presents time spent in 'distracting' or 'productive' applications Framing effects [118] Ko et al 2016 [93] Lock n' LoL, a smartphone app which lets users as a group set their phones in a lock mode in which notifications are muted and usage restricted None Ruan et al 2016 [154] PreventDark, an Android app which detects phone use in the dark and notifies the user that they should put it away None Whittaker et al 2016 [195] MeTime, a computer application providing a floating visualisation of time spent in different applications within the last 30 mins PomodoLock, a PC and Android application plus Chrome extension which blocks distracting apps and websites during 25 minute focus sessions Strength model of self-control [18] Marotta et al 2017 [117] Freedom, a commercial Windows/Mac/Android/iOS app which blocks access to distracting parts of the web or the internet altogether Rational choice, 'self-commitment' [31] Kovacs et al 2018 [97] HabitLab, a Chrome extension in which the user sets time limit goals for specific sites, then tries a range of interventions to reach the goal Numerous, including goal setting theory [106], operant conditioning [16]<...>…”