Best to-do and list app with sharing?

[brayhite]

I'm looking for the best to-do and list app with sharing capabilities.

I've used Trello, am using Remember the Milk now. I've looked a little into Clear and Things, and haven't heard anything amazing about Wunderlist or Omnifocus (not to mention I'm not looking to spend $100 upfront).

The things I'm looking for most are:

-collaboration abilities with another user(s)
-syncing among devices (web, iPhone, iPad)
-tasks AND list making capabilities

What I'd like, but not required, are:
-notification support (Mountain Lion and/or iOS)
-linking tasks together (Do X first, then do Y)
-attachment support for tasks

Subscription or one-time cost doesn't matter. If the product is amazing and does it all, I'll consider it.

TIA

[2012Tony2012]

I use Wunderlist and love it.

[jojoba]

While it's not actually a task manager, the premium version of Evernote might help you. Then you can share notes/ notebooks, where it's possible to add check boxes, bullet lists and so on, with seamless sync across platforms. You could use tagging to sequence different tasks, and it's easy to add attachments.

Personally, I use OmniFocus and SmallTask, but I don't think either meet your collaboration requirements.

[udontno]

I like Wunderlist. I know you can share lists, which is something that I like.

I've started using iProcrastinate for schoolwork and I really like that you can add "steps" to tasks. I wish Wunderlist would incorporate this in the future. For now, I'm going back and forth between the two.

[2012Tony2012]

Originally Posted by udontno

I like Wunderlist. I know you can share lists, which is something that I like....

Agreed!