Function phone_does 

fn phone_does() -> Phone

What this phone does itself, for whom Sioul’s modes let through: it screens calls (Sioul holds the role). A computer nothing. Nothing of the listener, though it may hold other apps’ notifications: Android plays a notification’s sound before any listener hears of it (docs/android.md, “Notifications from other apps”, Sound), so a contact’s message let through the mode and then held by Sioul would ring once in a pause or Free time; the mode is what keeps it silent. Calls differ: the screening answers before the phone rings.