CaseGuide: Making Cheap Smartphones Accessible to Individuals with Visual Impairments in Informal Settlements
Roos van Greevenbroek · 2020 · Proceedings of the 22nd International ACM SIGACCESS Conference on Computers and Accessibility (ASSETS 2020) · doi:10.1145/3373625.3417076
Summary
This short paper presents CaseGuide, a low-cost concept for making cheap smartphones accessible to individuals with visual impairments living in informal settlements (IVIIS). The majority of visually impaired people live in low-income areas where less than 5-15% can access assistive technologies, and smartphones under 50 dollars typically lack basic accessibility features like reliable screen readers. IVIIS depend heavily on others for navigation, employment, education, finances, and social contacts — dependencies that impose exclusion and vulnerability. The concept combines two components: a silicone phone case with a basic tactile keypad (raised buttons with a dot on the 5 key, four-directional navigation, dedicated screen reader and voice command buttons, and a keycord for theft prevention) paired with a launcher app that reformats all screens into a simplified, hierarchical, high-contrast interface. Designed specifically for the Neon Kicka 4 (Kenya's most purchased cheap smartphone), the app uses large white text on black backgrounds, vertical information lists, and a consistent one-option-at-a-time navigation structure to reduce cognitive load. The research was informed by an observational study of 34 YouTube videos (252 minutes, from 138 candidate videos spanning 2010-2020) featuring IVIIS using phones, analyzed using Braun and Clark's thematic analysis. Four themes emerged: phones as "success objects," exclusion due to assistive technology costs and compatibility, the challenging physical environment of informal settlements, and the vulnerable position IVIIS hold.
Key findings
A Wizard-of-Oz user test was conducted with three participants: one European with severe near-sightedness and astigmatism, and two sighted Europeans blindfolded to simulate blindness. Participants performed an unfamiliar task — buying phone credits using M-PESA (a critical mobile money service in informal settlements). Positive results included: participants found the tactile phone case helpful for locating, distinguishing, and navigating between buttons ("It is nice to feel what I'm pressing and to control the smartphone this way"); the hierarchical static overlay simplified navigation ("The screen-reader is so short I quickly know where I am"); and participants could independently complete the M-PESA task. Familiar gestures like pressing top/bottom were intuitive, likened to a remote control. Challenges included difficulty distinguishing different button functions, desire for more haptic/sound feedback, reading difficulties for the near-sighted participant who wanted bigger text and more contrast, and uncertainty about whether the static overlay could work with complex apps. The keycord theft-prevention feature addressed a real concern — the YouTube video analysis revealed IVIIS worried about smartphone theft due to their vulnerability.
Relevance
CaseGuide addresses a critical gap at the intersection of visual accessibility and global development: the 285 million visually impaired people worldwide, most of whom live in low-income settings where mainstream accessible smartphones (iPhone, high-end Android) are unaffordable. As basic/feature phones decline and smartphone use in low-income countries is expected to triple, the need for affordable smartphone accessibility solutions is urgent. The two-component approach — physical case for tactile input plus software overlay for simplified output — is pragmatic because it works with existing cheap hardware rather than requiring expensive accessible devices. For accessibility practitioners working in global contexts, this paper highlights that accessibility solutions must account for economic constraints, infrastructure limitations (unreliable electricity for charging), physical environmental challenges, and security concerns that are absent from high-income-country research. Significant limitations include the very early-stage prototype, the lack of testing with actual IVIIS (due to COVID-19), the use of blindfolded participants rather than blind users, and the design being specific to a single phone model.
Tags: visual accessibility · mobile accessibility · global accessibility · Global South accessibility · assistive technology · digital divide · low vision · digital financial inclusion · inclusive design