You can create different set of rules(Profile) for your need. Like profile "Working hours", "Weekend" and so on.
Use cases:
1. You only want to have the missed call reminder in non-working hours, you can set the time(6pm-11:59pm) and day(sat/sun).
2. You only want to reply as soon as possible for certain people. You can create a White List and set it to the Profile. You also can ignore Unknown Phone number by choosing the option in the Profile.
3. You don't want to be disturbed in a silent mode. You can configure it in the Profile.
4. What happen if your phone is plugged in the headphone ? There is an option for you to either play though the speaker or not.
5. Do you want to have different ringtone and volume for different Profile ? Yes, you can.
6. The Ringtone playing period and interval all are configurable in the Profile either.
7. Looking for the guide ? Just swipe to the left from the screen and you can see the guide with screenshots.