Is there an organizer that meets my requirements?

Question

Task Management

Prompt an organizer that meets the following requirements:
A plan with priorities and subpriorities.
Birthday calendar (export from Google, and better synchronization).
Calendar of daily events with the ability to create recurring events.
Notifications to the desktop, mail, but so that you do not have to constantly keep the program open. Or at least let it hang in the tray.
Android client (for notifications, the rest is not important).
Ability to record tasks and combine them into categories.
Of course, it's great if it works with the cloud.
Free.

Answer 1

LeaderTask is an excellent planner. You can see and evaluate if it suits you.