Can every Spectacles Lens use every device feature?

Treat dependencies as a feature list

Name each capability required by the Lens: the input, rendering behavior, permissions and any network service. Then identify the supported device and runtime for each. This is more useful than discovering a missing dependency after most of the interface is written.

If an optional input is unavailable, decide whether the Lens can still offer a smaller useful experience. If that input is essential, explain the requirement before the user begins. A blank scene is a poor substitute for telling someone that their configuration does not support the feature.