For me, todos wouldn't add much. Todos require something with more sophistication than any calendaring apps I use (BusyCal, iCal or GoogleCal, all at different times.); I use Things, and could probably stand to move to OmniFocus.
You can't beat the frictionless entry of a native application, and it's probably not worth trying. Right now, with some improvements, I can see your app as a way to either replace my current calendar (doubtful right now…native + natural language entry via AlfredApp and QuickCal is hard to beat), OR a way to fluidly plan my day/week in real-time, changing it as I need it. A way, more than anything else, to keep me focused by shooing out any thoughts of planning.
But I may not be your ideal user, and this would be a new tool with efficacy TBD.
You can't beat the frictionless entry of a native application, and it's probably not worth trying. Right now, with some improvements, I can see your app as a way to either replace my current calendar (doubtful right now…native + natural language entry via AlfredApp and QuickCal is hard to beat), OR a way to fluidly plan my day/week in real-time, changing it as I need it. A way, more than anything else, to keep me focused by shooing out any thoughts of planning.
But I may not be your ideal user, and this would be a new tool with efficacy TBD.