Good reminder/task manager?

Question

Notifications

Good day to all!
You can recommend a reminder or task manager you have tested (preferably cross-platform). From the functionality, I would like a reminder by email !!!, to-do !!, offline!.
If you have any in your arsenal, please write the advantages of this application (or maybe some kind of online service, web application).

Answer 1

Todoist

Answer 2

I tried it for 10 different pieces, including the Todoist listed here. I settled on Microsoft To Do.
Available as Android/iOS mobile applications, desktop on Windows, web version. Everything is in the cloud, all functions are free, there are notification reminders, you can combine tasks into lists, and lists into groups. Separately, you can see the list of tasks for today (the tasks you select are sent there) and the list of important tasks (there are all the tasks that you marked as important).
The tasks themselves can be divided into separate steps (and mark the completion by steps), also indicate an additional text note, assign a time for completion, automatically create a task on specified days (for example, once every N days/weeks/months or on weekdays) and that especially nice to attach files (no more than 25MB in total per task).
In addition, it has the best minimalistic design among all similar applications and a dark theme. No interface clutter.

Answer 3

wunderlist
microsoft todo
asana

Answer 4

I can add leadertask to those above. I like their reminder system in general. Comfortable. The web version is the same. But there is both offline and online mode and everything else that you mentioned.