Open TickTick on your iPhone, then go to the Calendar View. The standard view is free to use, other four views are premium only. You can pull down in the standard view to see a full calendar.
Tap the button at the top right corner to unfold five options and select to switch to another view. For example, the monthly view.
In any timeline view (day, 3-day, week), you can use pinch to zoom to adjust for a better view.