iPhone OS 3.0 brings a lot of new features to the table, but I could’ve easily gone on living without all of them, copy and paste included, except for push notifications. Push is the killer feature that elevates the iPhone platform to a whole new level of usability, both as a standalone device, and as a piece of companion hardware to your existing workstation setup.

The iPhone has taken the place of an entire screen in my current home office configuration, freeing up a whole display for more productive use. Here’s a breakdown of the apps that make this possible, and how I use them.

Beejive IM — Death of the Desktop IM Client

For me, IM can be a terrible time thief. Generally speaking, I intend to use it primarily for professional purposes, especially during the day, but having a desktop client constantly open and in plain view, it becomes hard to resist the urge to chat with a pal who’s just popped on for the first time in a few months, for example.

Thanks to Beejive with Push for the iPhone, the temptation isn’t nearly as strong to engage in distracting IM conversations. Using Beejive, I have an always-on solution that can stay out of sight, and therefore, out of mind. Even if someone contacts me, I find it much easier to politely ignore their advances when they come via my iPhone than when messages pop up on my computer’s display.

Remember The Milk — Task Management I’ll Actually Use

I have a problem with most GTD apps. Actually, the problem is more with me than with the apps. I just don’t use them, for whatever reason, for any length of time. I’ve tried a wide variety, but no combination of features seems to result in an experience that I’ll stick with.

Push has changed that. With Remember The Milk (Toodledo also offers push notifications, if you’re more inclined that way), I get an alert at a scheduled time when a task is coming due. It’s a small thing, but it’s enough to make the difference between paying attention to my task management software and not. It keeps me on schedule when I’m working at home or on the road.

Prowl — Growl Goes Mobile

Growl is a great utility for when I’m actually seated in front of my main work computer. It’s an OS X notification utility that works with an incredibly long list of applications to keep you informed, even when app windows aren’t in the foreground. What Prowl does is take some or all of those alerts and turn them into push notifications that you receive on your iPhone.

Which means that regardless of what I’m doing or where I am, I can be aware of anything my home workstation wants me to know. This includes Twitter @ mentions and direct messages — a much-requested push feature from iPhone Twitter users — and push email notifications that actually display the title and content of a message, rather than just modifying the icon like the iPhone’s built-in Mail app currently does. That means less time spent opening and checking emails that may or may not require immediate action, and more time focused on the task at hand. Best of all, you can set priorities and arrange it so that you won’t receive push notifications unless you’re actually away from your computer, to reduce redundancy and fluff.

The iPhone Arrives as a Business Tool

Not that I wasn’t using the iPhone for work before, but this is the first time it’s acquired the status of an integral part of my web working machinery. Heretofore, it’s been a nice, supplemental nice-to-have, but push is the killer feature that makes it a necessary device. Kudos, Apple, for providing an update that’s only just begun to hint at its eventual utility.

What do you think about Apple’s implementation of push on the iPhone? Do you find your device more useful now, or, if you don’t own one, does it add to the phone’s appeal?

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The web site is nicely designed and registering for it is straightforward. While registering, you set up defaults for your alerts — how you’d like to be reminded (email, SMS or both) and how far in advance of each task you’d like to be reminded.

You have two choices for entering tasks: natural language input and “Advanced” (manual input). The default is natural language input, which is fast and works pretty well if you stick to simple sentences and follow the format provided in the example. Unfortunately, once you stray a little from the example format, it falls down, and you have to go in and edit the task. For example, if you try to enter “meeting with Dave in 30 minutes”, it sets a task of “meeting with Dave in 0 minutes” for 3 a.m. on the current day. Natural language processing like this is a really tricky thing to get right, and Task.fm is still only in beta, but having to switch to manual input to re-enter tasks would get annoying fast. It’s also somewhat limiting to have to enter your reminders through the web app. With natural language input, I would like to be able to set reminders on the go through email, SMS or even voice input.

Once your reminders are set, it’s easy to manage and edit them. SMS and email alerts are timely and work just as you would expect, but I couldn’t find a way to set up phone call alerts.

Email reminders are free, but SMS and phone alerts cost 1 credit each. The cost of a credit varies depending on how many you buy, starting at 20 credits for $2. New accounts come with 10 credits, so you can try the SMS reminders for free.

Task.fm shows some promise with its simple, easy-to-use interface, but until the natural language input can deal with everything its users are likely to throw at it, I don’t believe it’s ready for widespread use (I Want Sandy — unfortunately now shuttered — was a great example of simple sematic input done right). I’ll be sticking with Google Calendar for my alerts.

What reminders app do you use?

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