Standalone is a brand new feature for the Misfit app version 2.8.0 and up. This is available on both iOS and Android.
With standalone, you can now track your steps and sleep just with the Misfit app alone. Simply go to Devices > (+) > Don't have a device yet? > Track My Motion > OK to enable step tracking. Afterwards, when you are ready to sleep, go to Home > Sleep > I'm ready > follow the on-screen instructions to kick start the sleep tracking.