App stability is just one aspect of app quality, which can be compromised by various factors beyond crashes, such as slow performance and poor user experience. Developers are encouraged to monitor key performance metrics, including app launch times, UI responsiveness, network performance, screen loading times, and execution traces, to ensure a smooth user experience. The Application Performance Index (Apdex) score is highlighted as a valuable industry-standard metric that measures user satisfaction by integrating multiple performance inputs, such as speed and stability, into a single score ranging from 0 to 1. Apdex allows developers to set specific performance thresholds and create alerts, providing a more comprehensive view of app performance than traditional KPIs. By using tools like Luciq's App Performance Monitoring, developers can track these metrics and optimize app performance, ultimately improving user retention and satisfaction.