PeerOnCall: Implementing and Evaluating App-Based Peer Support in Canadian Fire Services

The goal of this clinical trial is to test how best to implement a mobile peer support app called PeerOnCall in Canadian fire services. The main questions it aims to answer are: 1. Do firefighters use the app more with a structured implementation compared to standard implementation? 2. Does using the app improve mental health and workplace outcomes? Researchers will compare a standard implementation approach with basic onboarding to more structured implementation with weekly reminders, new content, and feedback reports to see if these features encourage more consistent app use. Participants will: 1. Use the PeerOnCall app to access private peer support and wellness resources. 2. Participate in surveys, interviews, and focus groups about their app experience and workplace environment.