“…Several meta-analyses of educational interventions in Sub-Saharan West African contexts found that investments in instructional technology-specifically, adaptive instructional technologies-had the largest effect sizes for improving student learning outcomes, compared with funding nutritional and health interventions, reducing class sizes, or providing financial incentives for attendance [15,54]. Educational technologies have been deployed in many low-resource communities, using mobile devices in class [83], after school [35], across contexts [41,64,82], or using apps on e-readers [71] or tablets used in schools [62] or in both schools and home [81]. However, with few exceptions (e.g., [35,64]), these systems have been designed for smart devices [33,41,60,81,83], despite significantly fewer families in rural communities owning smartphones than low-cost feature phones [48,49].…”