PrepToPay is a mobile app built for payroll professionals studying for the FPC and CPP certification exams through PayrollOrg. Built around the actual exam domains — all seven — with 1,270+ practice questions, a 20-question diagnostic that finds weak spots on day one, and spaced repetition so you retain what you learn. Free tier with no expiration. Paid plans add full study paths and progress tracking. Available on iOS and Android.