Ive been using Cal with Any.DO for about a week and its been very useful. The presentation is clean, the integration between Any.DO and Cal works well. Ive not had any issues adding calendar items and find it a bit more simple than iCal. It works with Waze well. Whatever bugs there may have been in 2015 (based on other reviews) seem to have been fixed. I think Cal is a really great app (and Im not easy to please!) and well worth using.
mollymissme about Cal – Shared Calendar, Daily Organizer, Weekly Planner, v1.5.4