If you are recording a workout through the Stryd app, other functions on Apple Watch may be limited.
Stryd app will allow for most background apps and processes to run while the Stryd app is visible on-screen. Bluetooth connectivity and data reporting from your Stryd footpod will be paused if you navigate away from the Stryd app during an actively recording run. This is a requirement of Apple’s WatchOS.
Stryd app will not be compatible if primarily running in the background with another app on-screen. Some examples of process that will not interact well with Stryd's workout recording are other real-time activity tracker app attempting to provide running metrics about your current workout-- such as heart rate, elevation gain, or GPS location on topographical maps.