Everyone knows that developer's wanted an SDK for the iPhone, and most were disappointed whein Apple told them to use the web instead. But not all is lost, there's already some cool web-based apps for the iPhone and more are popping up everyday. 

Here's a roundup of iPhone optimized apps to get the functionality Apple isn't offering.

##Widgets

Given the small screen size, the iPhone is ideal for widgets, small apps that do one thing and one thing well.

First up is <a href="http://m.widgetop.com/">Widgetop</a>, a slick web-app that replicates Apple's Dashboard interface on your iPhone. Handy widgets give you quick access to Wikipedia searches, RSS feeds and a much better looking sticky notes application with customizable fonts and colors.

Some of the apps in Widgetop duplicate features already on the iPhone, but there's some unique offerings as well. The widget directory also includes dozens of customized apps ranging from webcams to quote-of-the-day widgets. 

Signing up at the site will allow you to create a customized widget layout and save your content.

It would nice to see some widgets that allowed two-way sync for popular web services like del.icio.us or Flickr, but so far there isn't.

Another entry in the widget space is <a href="http://www.kudit.com/">Kudit.com</a>, but regrettably the services aren't free. There's some nice fun apps, but the listings are nowhere near as extensive as Widgetop and really, who wants to pay $2 for a magic eight-ball app?

##Games

Rather surprisingly, since even the iPod has a few, the iPhone doesn't ship with any cool time-wasting games to help you through those boring commutes.

But never fear, the web delivers. So long as you have a decent Wifi connection, there's <a href="">Sudoku</a> for the iPhone as well as <a href="">Chess</a> and <a href="http://www.hahanotsofunny.com/iphonegames/tictactoe/">Tic Tac Toe</a>. 

Okay, so it's not Halo, but Diamenty is a very addicting bejeweled-like game made for the iPhone. 

There are also dozens of other small games available through Widgetop's interface.

##Chat Services

iChat for iPhone is web-based solution of users looking for those missing IM features. IChat for iPhone is written in JavaScript and allows for web-based chats on the AIM network. While it's ideal with a wireless connection, it's not too bad even over EDGE. 

The source is available and can be hosted on your own server for better security, but if you'd like to take it for a spin, point your iPhone to <a href="http://www.publictivity.com/iPhoneChat/">Publictivity</a> which is hosting a demo version. You're limited to a ten minute session and the site warns that service may be intermittent, but I haven't had any problems.

What if you're not an AIM user? No need to worry, iPhone ships with a "full-fledge" browser. Just fire up Safari and head over to <a href="http://wwwm.meebo.com/">Meebo.com</a>. It may not be optimized for the iPhone (yet), but it works just fine and supports all the major chat networks including AIM, MSN, Yahoo, ICQ and more.

##Office Applications

Even before the iPhone was released the developers over at Zoho had hacked together an iPhone optimized version of the site.

<a href="http://mini.zoho.com/">IZoho</a>, as the iPhone optimized version is called, offers access to Zoho Writer, Sheet, Show and Creator, though only Writer has read and write support thus far. The Zoho Team reports they're working on read/write support for the others as well, but for the time being you'll have to settle for reading your documents.

IZoho performed admirably in our testing, but it's definitely one for Wifi, it took the better part of ten minutes to fully load the Writer editing interface over AT&T's EDGE network.

##RSS

On the eve of the iPhone's release curious snoopers discovered a page on Apple's site that seemed to indicate there would an <a href="http://reader.mac.com/">iPhone optimized RSS application</a> in the works. That speculation may be correct, but for now the page simply advertises Safari's built in RSS reader capabilities.

However, a number of small widgets for collecting news feeds on your iPhone have already sprung up. Widgetop offers a feed reader, but of course Google Reader is probably the best known web-based RSS reader. 

While Google Reader offers a mobile version of the app, David Cann has developed a very nice <a href="http://davidcann.com/iPhonify/GoogleReader/">skin for Google Reader</a> which aims to make for easier browsing on the iPhone.

Because Cann's Google Reader skin is actually a Javascript bookmarklet you'll need to drag the link up to the tool bar in Safari and then sync that link with your iPhone via iTunes. 

From there, just navigate to the Google Reader homepage (the standard version, not the mobile version), open your bookmarks and hint the bookmarklet for the skin. This will cause Google Reader to reload and display your subscriptions as a narrow list which you can navigate by tunneling in horizontally.

The interface is well done and works much better than the default mobile version Google offers, but a word of warning -- this one has crashed my iPhone version of safari a couple times.

##Lists

The iPhone's portability makes it an ideal place to store your to-do lists, which makes Apple's decision not to offer syncing capabilities all the more curious (speculation contends this decision has to do with the upcoming system wide list tools in Leopard).

That's okay though, by far the simplest app in this list and, perhaps not coincidentally the most useful is <a href="http://onetrip.org/apps/desktop.php?onetrip">OneTrip</a>, an ingenious interface for quickly organizing and building a shopping list on your phone. So far as we know this was the first third party app for the iPhone.

OneTrip is easy to use, just point your phone to the site and you can build a shopping list in no time. Then, when you're at the store, just check off items as you find them.

Thanks to cookies OneTrip will remember what you still need to get next time you visit the site.

##Misc

How about accessing your del.icio.us account through the iPhone? Yup, there's an <a href="http://gobekdeligi.com/idelicious/">iPhonified version of del.icio.us</a> available.

Other nice apps include <a href="http://showtimes.optimalconnection.net/">Showtimes<a/>, a quicker way to find nearby movie listings by zip code, <a href="http://www.chandlerkent.com/iphlickr/">iPhlickr</a> makes it easy to browser the photo sharing site via the iPhone and <a href="http://www.widgetinfo.net/iphone/">iActu</a> is very nice looking news browsing site optimized for the small screen.