We present Speeching, a mobile application that uses crowdsourcing to support the self-monitoring and management of speech and voice issues for people with Parkinson's (PwP). The application allows participants to audio record short voice tasks, which are then rated and assessed by crowd workers. Speeching then feeds these results back to provide users with examples of how they were perceived by listeners unconnected to them (thus not used to their speech patterns). We conducted our study in two phases. First we assessed the feasibility of utilising the crowd to provide ratings of speech and voice that are comparable to those of experts. We then conducted a trial to evaluate how the provision of feedback, using Speeching, was valued by PwP. Our study highlights how applications like Speeching open up new opportunities for self-monitoring in digital health and wellbeing, and provide a means for those without regular access to clinical assessment services to practice-and get meaningful feedback on-their speech.