I use OmniFocus, in spite of their bad UI and general priceyness.

* Things: has a lot of things going for it, but syncing is terrible. You can't directly sync from iPhone to iPad for example without having a copy of Things.app on Mac on your local LAN. If you're only using one device, I guess this doesn't matter, but it's a big deal for me. I seriously tried to switch to Things, since it was so much easier than OF, but the syncing support sent me back within a week.

* RTM: No projects support (tasks inside tasks). This is a dealbreaker for me, since I like to organize my tasks into groups. RTM just seems really lightweight to me for organizing my whole life.

* ToodleDo - sync is a problem again. It syncs to RTM, but you have the same projects problem. It syncs over Bonjour/WiFi, but you have the same Things problem.

OF's UI is terrible, but it is powerful and can basically be configured to work however you want. I wish there was a more painless way to do start/end dates for tasks like Things, and I wish they had a native iPad client. And I wish they moved towards tags and away from tree hierarchies. But overall, not bad.

I'm surprised not to see anybody mention Nozbe.

It's been around quite a while as a web app, and does a great job of balancing simplicity with functionality and features. The web interface is excellent for just letting you get on with what you want to do - i.e. things work just as you'd expect, and there are no frustrating UI punishments for doing things 'the wrong way'. The iPhone counterpart has recently had a major overhaul and is now just as slick and easy to use.

It's pretty hacker friendly, too - for example, you can export all your task info to a plaintext file, edit it however you like, and later re-import. There's a simple syntax for adding new tasks with metadata by email or Twitter.

I'd highly recommend giving it a try.

I enjoy GeeTasksPro from a HN contributor. It's synced with your Google Tasks, including GAFYD accounts.

http://itunes.apple.com/us/app/geetaskspro-google-tasks-app/...

I use Pocket Informant (http://www.pocketinformant.com/). It is kind of GTD-based (though flexible enough to accomodate other workflows), synchs with Toodledo for tasks and Google Calendar for Calendar, has push notifications. Last time I checked it had a free lite version but after using it for a little while I did not hesitate buying a full version.

I used to use (already mentioned) Zenbe lists for TODOs, but since then I migrated all TODOs to Pocket Informant. Zenbe Lists is great but is not really a task management app. I still use Zenbe for nice-to-do things and checklists like 'movies to watch', 'books to read', 'groceries', 'travel packlist' etc.

I bought Things and have been loving it. It's simple, intuitive and syncs with Things on OS X.

Zenbe Lists 2.0 was just released last night...

It's dirt-simple checklists with cloud sync, and their web UI is pretty good.

I don't need the fancy GTD or GPS stuff--just let me bang out a list, order the contents, check em off as they're finished--and gimme a web UI when I'm at my desk.

Last night they finally upgraded the app for iOS4 compatibility--it never worked right with iPhone OS 3. Hopefully they stay on top of future iOS releases (been waiting over a year for last night's release--thought it would never happen, was a pleasant surprise).

http://lists.zenbe.com

Things gets my vote. The syncing gets to be a pain, but I have the Mac, iPhone (ipod touch actually), and iPad versions so I just leave a Mac on. I also have 2 macs synchronized through dropbox (which is also a pain when you get conflicts).

I've tried RTM, TeuxDeux, among others, and they just aren't as amazingly intuitive as Things. There's something about the interface and the way it's set up that just completely gets out of your way so you spend less time tinkering with your task manager, and more time doing the stuff on it.

If they could get cloud sync, it would be perfect

I use Toodledo for long term things. Toodledo has the most flexibility for complex tasks. They also are a very customer-friendly shop so I like to support them, but their iPhone interface is not great for quickies. I use them for stuff I would use a computer for anyway, and tasks that I want a history of, even after I have done them.

I use a shortcut to google tasks for the equivalent of post-it-notes, i.e. stuff I want to flush out of my brain and do in the next few hours. Nothing that would carry over for more than a day, and stuff that once done, I delete.

I use OmniFocus for iPhone and I also have OmniFocus on my laptop. Both are syncing over the air to a database in LDAP dir on my own server.

Setup is definitely geeky, but at the time I decided to go for Omnifocus, none of the competitors could do it in a such way that I would have non-network access from my iPhone and laptop + over-the-internet sync between laptop and iPhone.

OmniFocus has all the stuff that you need to do for GTD style task (task, context, project). UI would benefit from a simplification, but I think it's good enough as it is.

Todo, syncing with ToodleDo's annual subscription for sync and web access.

I own Things, OmniFocus, Todo, and others, and at the moment, I prefer Todo. My objective is simplicity of entry with "GTD" style task management, with OTA sync across multiple Macs and devices.

For non-techies with just one Mac and one iDevice, I tend to recommend Things, while for sales, I tend to recommend Daylite.

(LAN WiFi sync doesn't count, only OTA sync ensures you're up to date.)

I've tried just about everything - OmniFocus, ToodleDo, Things, ToDo, Remember The Milk, etc. What really worked for me though was Unfuddle (free both online and iPhone).

It's a software project management system - which sounds complicated - but I found it to be the most intuitive. It allows me to manage all my tasks (programming, bugs, personal) in one place and I always like apps that have online/iPhone components.

P.S. Unlimited SVN and GIT repos too :)

I use ToDo (iPhone: http://itunes.apple.com/us/app/todo/id282778557?mt=8 and iPad: http://itunes.apple.com/us/app/todo-for-ipad/id371787147?mt=... ). They work great and have good sync support with ToodleDo. The iPad version especially is so useful that it's on my dock.

I like OmniFocus for iPhone, and find it to be the perfect companion to OmniFocus running on my laptop:

http://www.omnigroup.com/products/omnifocus_for_iphone/

Hunny Do is a nice collaborative application for sharing lists.Works great with your spouse. And it's free for iPhone.

I like OmniFocus for iPhone, and find it to be the perfect companion to OmniFocus running on my laptop:

http://www.omnigroup.com/products/omnifocus_for_iphone/