Community-Based Management of Acute Malnutrition (CMAM) is a proven high impact and cost-effective approach in large-scale detection and treatment of undernutrition. However, the success of CMAM programmes is usually undermined by lack of adherence to admission and treatment protocols by health workers as a result of poor reporting and follow up. Therefore, this study aimed to determine the effectiveness of mobile health (mHealth) in improving the screening and admission outcomes of the CMAM programme. A retrospective hospital-based cross-sectional study was done in 14 health facilities in Binga district, Zimbabwe where both pre- and post-intervention periods were studied. A paper checklist was used to collect the differences in errors between the paper based and mobile application. Project summary reports were used for collecting information on total screening and admission statistics between the comparison groups. Sensitivity and specificity rates were calculated using SPSS version 21. Error rates were 6.5% and 0.2% for the paper-based data management and mHealth application respectively. mHealth approach had a higher (1.0, 0.77) sensitivity in identifying cases with severe acute malnutrition (SAM) and moderate acute malnutrition (MAM) compared to the paper-based approach (0.81, 1.0). However, the specificity of the two methods were comparable. CMAM mHealth was effective in improving diagnostic accuracy and treatment outcomes in managing acute malnutrition. Hence, mHealth has the potential to improve the speed of response to surges in caseloads in this and related low-income settings.