High-end models (often found in Instant Pots or premium Crock-Pots) offer smart programming. You can program complex sequences, such as cooking on High for 2 hours, then switching to Low for 4 hours, then Keep Warm.
While timers are convenient, it is important to remember food safety. The USDA warns against leaving food in the "danger zone" (between 40°F and 140°F) for more than two hours. crock pot slow cooker with timer