If you've seen one Web-based collaboration tool, you've seen 'em all, right? That was my thinking, until I started seriously looking at Trello a few weeks ago. Trello takes the drudgery out of collaboration software. It gives users a Web-based workspace that's as easy to use as a whiteboard and Post-It notes, but full-featured enough for distributed teams that need to work on complex projects.

Trello is developed by Fog Creek Software, a company best known for developer-oriented software like FogBugz, and for co-founder Joel Spolsky.

The Idea Behind Trello: "Five Things"

When Trello was launched last year, Spolsky wrote that it came out of an idea at Fog Creek to help manage developers. "After ten years in management I still never knew what anyone was supposed to be working on. Once in a while I would walk around asking everyone what they were doing, and half the time, my reaction was 'why the hell are you working on THAT?' So one of the teams started working on finding better ways to keep track of who was working on what."

That led to the idea of Five Things. Every employee would have a list of exactly five things they were allowed to work on, two active jobs and three jobs that they'd tackle once the first two were finished. The number of things employees could be assigned was five, and no more. Four was too few, and six was right out.

Turns out, the Five Things idea didn't work so well, but it led to Trello. "We started dogfooding the product when it was only 700 lines of code, and even in that super-simple form, we found it incredibly useful. By the end of the summer, we realized we had a hit on our hands: an incredibly simple, easy-to-understand way for teams to collaborate online."

How Trello Works

Before we dig into the guts of Trello, let me explain why it's head and shoulders above any other online collaboration software I've tried. In a nutshell, Trello really is as easy as using a whiteboard and Post-It notes. It's great for visualizing tasks, and it's dead simple to use. A couple of clicks and keystrokes, and you've got an idea down or put an action item on your list. Moving cards around on the Trello boards is as simple as drag and drop. If the keyboard is more your thing, no self-respecting developer tool would be caught dead without extensive keyboard shortcuts, and Trello is no exception.

Now, let's back up to the basics of Trello. It provides users with boards, lists and cards. Each board starts with three lists, which can hold one or more cards. Boards can be used to organize any project - a software release, an editorial calendar, a user's to-do list or whatever you like.

The boards can be private, or belong to members of an organization, or you can make them public. If you'd like to get a quick idea of what a complex board might look like, the development board is a good one to start with.

Each list holds to-do items, suggestions, features or any other category you'd like to track. Cards track individual suggestions, features, etc. When you create a new board, Trello defaults to three lists: To Do, Doing, and Done. You can, of course, revise the names of the lists and add new ones. I'm not sure about the upper limit of lists per board - the Trello Development board has eight lists, which seems close to the upper limit that you'd want for a project whether or not the software will support more.

The individual cards hold (almost) as much, or as little, information as you'd like. At the most basic, you might give a card a title like "finish Trello article." Then move the card between the default lists to show what you're planning to do, what you're doing and what you have done. But cards will do much more for you, if you want.

Collaboration

Click on a card, and you can assign it to members of an organization, give it a due date, assign labels and leave comments. Cards also allow you to add checklists, so you could include a list of steps that need to be finished before a project is complete - or just use a card for your grocery list, if you like. Trello will also give a progress bar that shows how close a project is to completion based on the items that have been checked off.

As you'd expect, you can also leave comments on cards detailing your activities or leaving information for other members. Trello cards also allow for attachments up to 10MB, so you can leave documents, images, etc.

You might find more complete collaboration tools, but Trello seems to have struck the perfect balance between the amount of information that you can convey with the system and ease of use.

Trello also provides a full activity feed on the side of the interface, which shows what you (and other users in the same board) have done recently. You can also opt to have Trello send email notifications of activity "periodically" (about every hour) or "instantly" (every minute). You can also choose not to have notifications at all.

Finally, Trello also has really good filtering/search options so you can skim boards by keyword, member, label, etc. You can combine these, too - it's easy to search a board by label(s), member(s) and specific search strings.

Trello on Mobile and Add-Ons

The Trello experience works great on a desktop browser, but not so much on a less-than-5-inch screen. But as luck would have it, there's an app for that. At least, if you use iOS. The iOS app lets you do most of what you can do from the Web-based application. You can create cards, lists, etc. You can set due dates, add activity updates and so forth.

The Trello site works pretty well on the iPad in Mobile Safari, though it doesn't support drag and drop. You have to click the menu at the top of each card and select the "Move" option instead - not quite as slick, but still usable.

As far as I know, there's no Android app yet but it is in progress, according to the Trello team.

Work in Progress

It's worth noting that Trello is a work in progress in general. The team seems pretty busy adding features and responding to requests. Some very minor things don't work quite as you might hope. For example, you can archive lists, but you can't delete them outright.

You can print out cards, but as far as I can tell, not entire boards. You can also export cards as JSON, which might be nice for developers.

If there's a feature you think Trello should have, but doesn't, don't fret too much. Trello is in heavy development and Fog Creek has a really nice board for suggesting ideas and voting on existing ideas. I'm a little bit disappointed that Fog Creek isn't planning a paid or supported version of Trello in the near future. I'm pretty happy with Trello and plan to use it a great deal, so I'd like to be a paying customer rather than depend on a free product.

That said, Fog Creek has committed to keeping the current product free forever, though the company says it might add pay-only features in the future. It also has committed not to "make a for-pay feature that forces you to compromise on privacy, security or portability." So far, Fog Creek has had an excellent reputation with developers, so I'm willing to trust the company as it works toward a for-pay model.

If you're curious about how Fog Creek is putting all this awesome together, check out the tech stack behind Trello. It's an interesting collection of tech. And if you haven't tried Trello yet, what are you waiting for?