Remember when you had to click on an application to make it active, and hit refresh in order to find out if anything new had happened? It’s been a long while now, since most desktop programs can run in the background and notify you when something requires your attention. The iPhone approximates that same functionality via the newly introduced push notification features, though apps aren’t actually running in the background, so special support is required from app developers to enable it.
As far as I’m concerned, push has already been a game-changer. My iPhone is now my dedicated IM client, lets me monitor any and all Blue Jays games no matter where I am, and keeps me on-task with my to-do list. But that’s not all. Thanks to a new app called Prowl ($2.99, iTunes link), my iPhone can keep me abreast of pretty much anything, via my Mac and a useful app many will already be familiar with, Growl.
Growl, in case you aren’t aware, is an open notification platform for OS X that supports a wide variety of applications. Basically, it alerts you via an on-screen pop-up and/or sound when one of its supported applications receives a message, finishes a task, and so on. So, for example, using a Mail plugin, I receive a Growl notification whenever I get an email, or when I’m mentioned or receive a DM on Twitter via Tweetie’s built-in Growl support. It’s a very handy tool to have, especially if you keep your dock hidden, as I do, or if you’re working with many different applications on multiple screens.
Now you can receive Growl notifications on your iPhone, too, in the form of push notifications, thanks to Prowl. I can’t even begin to explain how useful this could potentially be, depending on your usage. Already, I have it set up to notify me of new mail (which works better than Apple’s (s aapl) wn push mail, in my opinion, because it allows me to see the sender and some content of the received message), let me know when I receive new @ replies and DMs via Twitter (which I can then check out in Tweetie), and alert me whenever Transmission finishes downloading or seeding a torrent file.
Not only can Prowl alert you of whatever Growl can, but it can also receive custom alerts sent from a web interface. When you set up Prowl, you sign up for an account that’s necessary for syncing Growl on your computer with Prowl on your iPhone. Using that same login, you can go to the Prowl web site and send yourself messages. Any applicable content in that message will be automatically hot-linked, like emails and phone numbers. Very handy for sending a contact number to yourself for future reference.
Prowl is potentially the most effective application of push I’ve yet seen on the iPhone platform, especially if you’re already using Growl (which you should be). The best part is that it’s limited only by Growl itself, which is infinitely expandable, so long as developers keep supporting it. Probably the best $3 I’ve ever spent in the App Store.