Hey Adrian,

From my understanding, the To-Do module in Odoo allows you to plan your tasks in one centralised place. Activity reminders may not sync directly with the To-Do app, but you can create activities for each to-do as well. These activities will be visible on the clock icon at the top right, depending on the date you select.

Moreover, you have the option to convert To-Dos into project tasks if you're using the project app. The To-Do app also supports stages, allowing you to move to-do from one stage to another. Additionally, you can create personal stages tailored to your specific needs, apart from the default stages and also you can use Tags to organise well.

I hope this information proves helpful. Thank you!