If I’m going all digital, Apple Reminders + Calendar.
For todos, I’ve been moving away from Reminders and using pen & paper with Analog (index cards). When I stumbled across Analog, it was setup almost exactly like my Reminders app (Today, Later, Someday), so it made the transition pretty painless. I just like being able to physically cross stuff off.
I do still keep some Later/Someday stuff in Reminders, because I don’t need that stuff everyday and I can add more context when needed.