The Coronavirus disease 2019 (COVID-19) pandemic has had a significant impact on education worldwide, affecting whether and how students learn. World Bank estimates and initial analysis at the country level indicate that school closures and interruptions to in-person education are likely to negatively impact student learning. Moreover, these estimates predict that students in low- and middle-income countries will suffer from more significant learning losses than students in high-income countries, worsening the existing global learning crisis. As part of their education response to the pandemic, many countries have provided learning content to students at home through various means, including through the internet via devices such as computers, tablets, and smartphones, as well as through television, radio, printed materials, and feature (basic) phones. With schools closed, teachers have also had to adapt to using these different media to continue their teaching. So, phone-based assessment solutions can be used for at least two purposes. The first purpose is to conduct formative assessment, for example to gauge how well students have absorbed the learning content, identify any misconceptions in understanding, provide constructive feedback to students or caregivers, and offer additional learning resources and activities to support learning. The second purpose is to conduct impact evaluations, for example analyzing the effect on student learning outcomes of interventions introduced in response to the pandemic.