Prevalence and Characteristics of Manipulative Design in Mobile Applications Used by Children

Key Points Question What types of manipulative design features exist in childrens’ mobile apps, and do inequities exist in young childrens exposure to manipulative design? Findings In this cross-sectional study of apps used by 160 children aged 3 to 5 years, the majority of apps were associated with manipulative design features that included parasocial relationship pressure, fabricated time pressure, navigation constraints, and use of attractive lures to encourage longer gameplay or more purchases, in addition to advertisement-based pressure; only 20% of apps had no manipulative design features. Children from lower socioeconomic strata played apps with more manipulative design. Meaning These results suggest that interactive designs that serve the interests of technology companies over the interests of children are common and deserve further study and regulation.


eAppendix 1. Coding Approach
Apps were selected based on having the longest duration of average daily use (top 3 per participant). Because we had 3 phases of app usage data, we started by using the top-duration apps from Phase 1. If a participant did not have Phase 1 device data, used less than 3 apps, or any of their top-duration apps were unavailable (i.e., had been removed from the app store) or uncodable (e.g., built-in apps that would not be expected to have manipulative design techniques such as texting, camera, clock, or browser), we selected additional top-duration apps using the same approach from Phase 2 and then Phase 3, in order to get 3 apps for each participant when possible.
Coders were instructed to play each app for about 10-15 minutes, completing several levels (if applicable) and visiting every available page (e.g, settings, store, level map) to observe for design abuses and ease of navigation. If a tutorial was available at the start of the app, coders were instructed to watch it to know how to play the game. Coders switched between apps during gameplay and returned to apps several days later to elicit any design abuses that occur when exiting or notifications prompting the user to return to the app. Coders also were idle for about 60 seconds during gameplay to elicit any reactions from the app regarding restarting playing. Coders additionally navigated to the store section of each app, if present, and took steps to purchase an item, which they cancelled right before confirming the purchase, to see if design abuses occurred in this context. When apps offered in-app items or rewards in exchange for ad viewing, coders watched several ads to describe how this occurred. After accruing in-game currency, they also purchased items (both which they could afford, and ones that were too expensive), to elicit how the app communicated with the player around these transactions. If apps required a free trial, coders created one with our research lab's email and waited through the free trial period to examine what pressure occurred to purchase the app. Coders did not code sections that were labeled as "for parents," as we presumed that these sections would not be designed with child users in mind.

NAVIGATION CONSTRAINTS (To prolong gameplay or encourage purchases)
These are UX features that constrain where you can go, or how easy it is to navigate around the game or know where you are/orient yourself. Examples of easy navigability include the app having a home screen that can always be accessed through a clearly marked button, a map that shows where you are relative to other levels, and easy "back" options that let you recover if you make the wrong decision.
Designs that contribute to worse navigability include lots of pop-up ads that get in the way of going to the next level or home screen; auto-advance without choices to pause or go back; minimization of buttons that avoid purchases or stop gameplay. You might get a sense of disorientation in the game that may result from lack of symmetry of UI features. It's unclear what will happen when buttons are clicked.
Note: it's OK if the app gives you a pre-determined # of free days or plays, and is clear with you about how many you have left. Also OK to have parent gate before purchases. These are appropriate navigation constraints, but if there are other manipulative features in addition to these, code a 1.

LURES (To prolong gameplay or encourage purchases)
Lures are tokens, rewards, candy, virtual toys, gameplay items, words (e.g., "hot item!" "popular choice!") or visual cues that try to attract attention and encourage behaviors (gameplay, purchases, clicking on ads). They can be present anywhere in the game experience, but often are at the end of a level (sometimes with a countdown timer), in the store/purchase area, or on the homepage.

INTERACTION WITH ADVERTISEMENTS
ROADBLOCK ADS exist when the ads force the player to watch them (stay up >20 sec with no "x"), prompt user to play them (sometimes with age-inappropriate or violent content), or navigate player to the app store. STRATEGICALLY TIMED ADS occur when an ad pops up when the player tries to go back to the home screen (i.e., stop playing) or X's out of a purchase -akin to a punishment for choosing to disengage.
ADS WITH REINFORCEMENT occur when the player is promised gameplay items, tokens, or rewards for watching ads.  * App name and screen shot appearance were used to identify specific apps for iOS devices; ** The number of users who had this app in their 3 top-duration apps; 999 indicates apps that did not have interactive characters and therefore were not coded for Parasocial Relationship Pressure; *** When data were collected (2018), TikTok was primarily for viewing music/dance so was not coded as an adult app