LeaderTask

Plan, assign, control! Any device, even offline!

Screenshots

Hunter's comment

Leadertask is your assistant for all your team works. You can make your to-do lists, create sub-tasks and reminders.

LeaderTask isn't just the program, it's also the guide to the world of time-management.
Source

Download links are as below:
Windows
Google Play
App Store

Link

https://www.leadertask.com/