The document describes the PRADA approach for prioritizing Android devices for apps by mining large-scale usage data. PRADA collects usage data from Wandoujia, clusters similar apps and device models, then applies collaborative filtering to accurately predict major device models for a new app. It was evaluated on two app categories and achieved satisfactory accuracy in device model hit rates and time share coverage. Future work could explore the impact of localization and different device model clustering granularities.