Essentially both ADT and SimpliSafe systems offer similar keypad functions on their monitored systems.
https://www.thehomesecurityadvisor.com/adt-vs-simplisafe-security-review/
OFF – Whether you select ADT or SimpliSafe, even when your system isn't armed the chime feature will still alert you if a door or window is opened.
Stay- Both SimpliSafe and ADT allow you the ability to arm just the perimeter protection at the doors and windows by setting the system in the “stay” mode.
Away- The away mode will activate any interior motion detectors as well as the doors and windows.
Instant – You can eliminate the entry delay on either a SimpliSafe or ADT security system by arming it in instant mode.
Duress - You can set up a special duress code with both the ADT and SimpliSafe monitoring centers to signal a potential hostage situation. So when comparing SimpliSafe vs ADT, you can arm as little or as much of the system as you wish.
https://www.thehomesecurityadvisor.com/adt-vs-simplisafe-security-review/