If you want a service that synchronizes your bills with your calendar and sends you reminders, Cushion could be the answer to your prayers. It lets you organize, track and calendarize your bills so you don't miss payments. It also has other features like credit score monitoring, payment through a virtual credit card and split bills, for $4.99 to $12.99 per month.
Another contender is Dola, an AI calendar assistant that works with Google Calendar and Apple Calendar. Dola lets you manage your personal and group calendars through conversational interactions, accepts multiple input formats and sends automated reminders. It's a good way to keep your calendar in order.
If you want a more general-purpose tool, Twos is an all-purpose information manager that includes calendar integration powered by AI. It can capture and track lots of aspects of your life, including tasks, reminders and calendar events, and offers daily lists and shared lists for organizing and sharing information. Twos is free to use, with optional upgrades, so it's a good way to consolidate your organizational tools.