So now most developers seem to be focused mainly on expanding existing apps to incorporate these capabilities. Here's a quick look at five applications that use these features.
The easiest way to track them down is by accessing the App Store on the iPhone and searching for the app title. (You can do it in iTunes, too, if you want.)
1. Push to jive: BeejiveIM 3.0 with Push
Beejive was an early developer for the iPhone; it even had a web-based instant messaging client before Apple released the APIs for building 'real' iPhone apps. What's new in Version 3.0 is push notification, one of the premier new features enabled with the release of iPhone OS 3.0.
What this means is that BeejiveIM 3.0 will let you know whether any of your IM accounts - AIM, iChat, MSN, Yahoo, FacebookIM, ICQ or Jabber - has an incoming message, whether you're currently running BeejiveIM or not.
Though there are other (and free) IM clients, BeejiveIM has one of the more integrated user interfaces, as well as a wealth of options, such as SMS out, hyperlink support, chat histories, and pop-up-ad blocking.
Though some people might not want to be available this way 24/7, it's nice to know you can be. (Note to BlackBerry and Windows Mobile users: Beejive has you covered as well.)
2. Fight the flip: Flickit
From: Green Volcano Software
Flickit allows you to take, tag, title and geotag multiple photos for uploading to your Flickr page. I've managed to avoid the Flickr phenomenon, since I'm not a shutterbug, but I can see how this would be wicked useful for those who are.
Best of all, it's even compatible with all previous hardware models and iPhone OS 2.2 or later.
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NEXT PAGE: AP Mobile and Star Defense
Apple's latest software for the iPhone - iPhone OS 3.0 - has added a wealth of new capabilities to the smartphone, such as push notifications and MMS support. We've rounded up five apps that make the most of these features
3. News you can't lose: AP Mobile
From: The Associated Press
You have to be a bit careful setting up AP Mobile initially - it takes advantage of the iPhone OS 3.0 push feature, so top stories can pop up at any time, requesting your attention, even when you're using another app, or no app at all.
You might want to disable that feature before going to, say, a job interview or a funeral. Otherwise, this is a great, free way to keep on top of breaking news.
4. Gaming heaven: Star Defense
From the same company that brought out other amazingly creative offerings like Dropship and Rolando comes this tower defence game.
Not only does it benefit from the iPhone 3GS's souped-up CPU and GPU chips, but it uses push notifications to send out challenges to friends and other Star Defense players within virtual earshot.
The Nintendo DS family of handheld game devices were immensely successful in their P2P play over Wi-Fi. There's no reason the iPhone and the iPod Touch can't also grow into using peer-to-peer/player-to-player networking for collaboration and challenges, opening up new modes of gameplay and productivity. One hopes.
5. What now?: Remember the Milk
Price: Free, but requires $25 (£15) 'Pro' account
From: Remember the Milk
Remember the Milk is a to-do productivity application that can get around one of the big weaknesses of most to-do lists - you have to look at them. I know that's a problem for me. For example, iCal can send you email or desktop note alerts, which helps - but it only works if you are at your desk.
This app will display an alert at user-defined times before a task must be done. The alert will arrive via IM, email or SMS. It works with Google Calendar , and you can manage tasks even if you're offline and you can share them, as well. It's like the way your mom would remind you to do homework when you were a kid.
These five are just the tip of the iceberg, given the thousands of apps available already and the countless others in the works. It took a little while after the initial APIs were released for developers to start really taking advantage of the iPhone's initial features, like multitouch functionality.
We'll be seeing more as time goes on, especially since by most metrics, the adoption rate has been fabulous for the new operating system - more so with iPhones, where it's free, than on the iPod Touch, for which there is a charge because of the way Apple accounts for revenue.
Let's just hope developers and users don't go overboard with the pushing. It could make a crowded train car quite annoying.
See also: The 16 best free iPhone Apps
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