Offer a combined month and day view
The app Fossify/Calendar offers quite a good example for this: https://github.com/FossifyOrg/Calendar/blob/master/fastlane/metadata/android/en-US/images/phoneScreenshots/4_en-US.png
With this I could have a good overview of both the month and the day.
Instead of having it above and below (because it's on mobile phones obviosly), we could have it side-by-side (left/right) on the computer.