https://9to5mac.com/2018/08/12/whats-the-best-calendar-app-for-iphone/
I live by the calendar on my iPhone. I use Gmail and Google Calendar on my desktop for a variety of reasons that I’ll talk about later. On my iPhone tho, I prefer the display and data entry features of Fantastical for my calendar. Clean entry, great incorporation of multiple calendars, and more.
This article describes the top calendar programs and does an excellent job of detailing the pluses and minuses of each with excellent screenshots. It may be time for you to switch. Enjoy!
Abycats' Thoughts 