That being said, we can't ignore the fact that other phones have made a big impact this year as well. Most notably, we have Android, Google's new mobile OS, first launched on the T-Mobile G1 and now coming to a very Blackberry-esque device in Australia. Thanks to Android's open source version, the question of how it will compare to iPhone has a simple answer: Android is open where the iPhone is closed.

This is the fifth in our series of top products of 2008:

1. Top 10 Semantic Web Products of 2008
2. Top 10 International Products of 2008
3. Top 10 Consumer Web Apps of 2008
4. Top 10 RSS and Syndication Products of 2008

With the above thoughts in mind, as we look back at the best mobile apps from 2008, we can't help but notice how iPhone apps top the list. Still, we've tried to include apps here that aren't iPhone-only so that we can deliver a truly well-rounded list. If we missed your favorite app (and surely we did - these lists are always subjective), let us know in the comments. Also, please note that we chose not to include games on this list - at this point, that's a whole other category.

1. Twitter

Without a doubt, Twitter is one of the best social networks to use on your mobile device. You can update your status, send replies, and engage in 140-character conversations from the palm of your hand by way of any number of mobile applications or even via SMS (in some countries, that is). However, it's hard to pick a clear winner in the category of best mobile Twitter application. Depending on your platform, there are multiple apps available and everyone has their own personal favorite.

In an informal poll on Twitter and FriendFeed, we saw some applications received more votes than others. Those included Twitterberry, which is the Twitter app for Blackberry it seems, and Tiny Twitter was popular among Windows Mobile users. For the iPhone, things were more complicated. There are several different applications available, but we noticed that TwitterFon and Tweetie got the most votes. Plus, the newer app Tweetsville is worth mentioning, too, as it has been getting a lot of buzz lately.

Earlier this year, we had polled the blogosphere on the same subject and found then that the top mobile app for Twitter was Hahlo. Only a few months later, and so much has changed. It seems that as new Twitter apps are released, mobile Twitter users rush to try them and often end up with a new favorite du jour. What ends up being your favorite app in the long run has a lot to do with personal preference as well as how you user Twitter. Power users may find the apps with more features to be the best, while casual users might prefer a more simplified interface. In the end, what's most telling about this trend to tweet from our mobiles is that it's not about one particular application. Instead, what's important is that nearly everyone is tweeting. That makes Twitter itself the mobile winner, no matter which application you use to interact with it.

Read some of our top Twitter articles from this past year:

How We Use Twitter for Journalism 

The Rise of Twitter as a Platform for Serious Discourse

How To Get Customer Service Via Twitter

2. FFtoGo

Let's face it, we're social media addicts, and this year, no other social network has been discussed quite as much as FriendFeed. Initially, there was concern that FriendFeed was relocating the conversations that used to take place on blogs and moving them elsewhere. The conversation has left the blogosphere, we cried. Not only that, but FriendFeed's stream of updates began to overwhelm even the best of us. It just became so noisy that the service began to lose its original luster after a while. But then things started to change. FriendFeed implemented dupe detection and bloggers (like us!) found ways to integrate it with their commenting mechanisms. When FriendFeed implemented lists in late August, we were sold. FriendFeed finally became more manageable and thus, more fun.

Of course, we didn't want to give up FriendFeed just because we were going to be away from our computers. That's where the mobile application FriendFeedToGo came in. Thanks to developer Benjamin Golub, we were given FFtoGo.com, a mobile interface for FriendFeed that soon became the interface of choice, even over the company's own iPhone version. Needless to say, those at FriendFeed knew a good thing when they saw one and soon swooped up Benjamin to join the rest of the FriendFeeders in downtown Mountain View, California. We couldn't have been more pleased.

3. Google Maps

What's one of the most important applications you need on a mobile phone? Maps! And when it comes down to it, the application of choice is Google Maps. This year, we saw Google launch their own mobile OS, code-named Android, and with it came one of the coolest applications we had yet seen: Google Maps with Street View for Mobile.

In September, Google updated their Google Maps for Mobile application, which brought Street View to non-Android phones including Blackberry and those phones powered by Java. There was only one glaring omission: the iPhone. Thankfully, iPhone owners finally received Street View, too, with the iPhone 2.2. firmware update, released in November. Google also released a mobile app with voice recognition that same month. These developments came much to the relief of iPhone users who had previously worried that Google was going to only release their coolest apps for Android. Thankfully, that wasn't the case.

Speaking of Google, we should also note that many of you said you couldn't live without your other Google apps, either. Google Reader and Gmail were also hugely popular apps across all mobile platforms this year.

4. Fring

The popular mobile IM and VOIP service Fring lets you access and interact with your social networks on the go, make free calls, and chat with your friends over IM - what more could you want in a mobile app? The service supports Skype, Windows Live Messenger (MSN Messenger), Google Talk, ICQ, SIP, Twitter, Yahoo!, and AIM, and all are made available over your phone's internet connection. With the Fring app, you can see who's online, have multiple conversations at once, and even send and receive files with your friends

Fring also launched an Application Programming Interface (API) earlier this year that offers the Fring mobile interface, IM, presence indication, file transfer and other features to developers seeking to build apps in standard server-side languages. Thanks to the fringAPI™, you can access an ever-expanding group of Fring add-ons including ones for Facebook, Gmail Notifier, Vtap Video Streaming, Orkut's Social Network, Yandex Push Email, and more.

Fring has long been a favorite app for iPhone - it was one of the top apps for jailbroken phones prior to the launch of the iPhone SDK. Strangely, though, there was a long delay between the July 11th opening of the iPhone app store and the October 2008 launch of the official Fring iPhone app.

It's also worth noting that Fring isn't an iPhone-only application - it's supported on a large number of handsets from many different carriers. To see if yours is supported go to m.fring.com.

5. Brightkite

Yes, the mobile social network Brightkite includes an iPhone app, but it's much more than a toy for the exclusive club of iPhone owners. The service, a device agnostic, SMS-based application, lets you "check in" at various locations out in the real world and then see who else is there, has been there, and who is nearby. You can check in via text, web,or iPhone, but text is easiest if you're using a traditional cell phone.

After checking in, you can post updates in a Twitter-like fashion and upload photos to your Brightkite-enabled stream, available at a URL in the format of brightkite.com/people/username. The newly launched "Wall" feature makes Brightkite ideal for conferences and live events as it allows anyone to display the live stream of notes, photos, and checkins at any one place in a large, full screen view that can be shown on any monitor, projector, or TV.

Brightkite isn't on this list because it's hugely successful in terms of numbers - it's here because of its potential. There's still some debate as to whether consumers really want new and separate social networks just for the mobile phone. As we noted back in October, no other social network, including those specialized for mobile devices, had even reached 15% adoption. That means Brightkite and others like it still have a way to go before they become a solid part of the new mobile web. However, if any of these apps have a chance for success, it's Brightkite. With the service's Twitter integration and live event niche, they offer something unique.

Brightkite's best competition comes from a similar app called Loopt, also a cross-platform tool. Loopt is popular with iPhone users - it made the list of top iPhone apps this year. We think Loopt's Android version is interesting, too, because it works in the background automatically checking you in as you travel from place to place. However, although Loopt is available on numerous phones and carriers in the U.S., Brightkite works on all phones. Also, whether people want an app with more automated tracking (like Loopt) or more control (like Brightkite) is yet to be seen.

As with any new application, Brightkite is still waiting to achieve critical mass. It's not mainstream yet, but it's definitely worth watching in 2009.