All assistants have a wake up word (e.g. "Hey Google"), so Dicio should have it, too. This should be doable with a service running in the background with Vosk that keeps listening. Athena already has this feature (video), we might take inspiration from it. The wake word recognizer should obviously be easy to enable/disable in settings, and should probably be implemented with a foreground service, so that newer Android versions do not force close it after a while.