Gathering patient-reported data enables physicians to know a patient and his/her health-related needs in a more comprehensive way. One method to collect these data is to let the patient fill out electronic questionnaires on a mobile device, e.g. a tablet. Although having successfully implemented a prototype, the mobile questionnaire system at this site has been stretched to its limits within both routine care and clinical trials. By collecting user feedback and analysing the capabilities and limits of the underlying framework, we identified key issues of the prototype. A new implementation addresses these obstacles while keeping the overall application logic and usability. This leads to a trial-ready mobile patient questionnaire system.