Core Buddy
Core Buddy picks the workout so you don't have to. Open it, press start, and it tells you what to do and times the whole thing. Bodyweight to begin with, dumbbells and kettlebells if you've got them.
There's a five-level programme called Level Up to work through if you want one. A randomiser, a follow-along library and HIIT Shapes for the days you'd rather not think about it. Every move has a video of me showing it.
Free to download, and the 30-day free trial covers the lot.