Nested Tasks

That's Outlook Tasks, not a "task/app manager"

It (pretty much) replaces all the functionality of the built-in Tasks application.
It adds the ability to nest tasks under one another
Based entirely on properties of the built-in Tasks - will sync with Exchange/Outlook, and requires no importing of Tasks

Installation:
Copy the Nested_Tasks.cab file to your device
Run it

General Usage:
On first use no Tasks will be nested (obviously)
Tap-and-hold on an item to be nested (the "Child"), choose Cut from the context menu
Tap-and-hold on an item to become the "Parent", choose Paste Here

Features:
Cut and Paste tasks to create nesting
Add new, edit and Delete tasks
Copy tasks to create duplicates
View and set task Priority from the menu
Complete or Activate Tasks with the checkboxes

Nested Tasks