There are an increasing number of applications for Blackberry smartphones that perform the same function. You have choices from the app store, freeware tools and small pieces of software put together by users like you and me. I'm going to pick four quality applications for your blackberry that are absolutely free to use.
TwitterBerry - No free app list for the blackberry is complete without a twitter application. There are a variety of applications that allow you to use Twitter on your blackberry with varying user interface refinements and workability. TwitterBerry manages to strike a good balance between functionality and eye candy. Very few keypresses are required to update your status. The timeline view is also optimal and searching also works well.
Facebook for Blackberry - The facebook application developed for Blackberry phones is fast loading and it manages to extend the web version of facebook to the blackberry. It allows you to view your wall posts and with a fast wi-fi connection, compressed versions of the online photos load instantly. It also allows you to upload pictures to your profile from your camera from within the application.
BerryQuery - This tiny little app searches for information from blackberry related sites. This includes app developers, review sites and the official RIM portal. It allows you to easily search and locate OTA links for applications that you may like and also email their links to yourself for downloading later. Using a slower connection you could find apps that you like using the search engine and its interface allows you to easily email the OTA links to yourself. Once you have access to a fast wi-fi connection you can download the apps from the links in your messages.
Google Maps -This is one application that I would not leave home without. If your phone lacks GPS connectivity, you could still browse maps using an available network connection. The My Location feature allows you to pinpoint your location without GPS connectivity using cell phone towers. You can search from within the interface and find out points of intrest such as ATM's, restaurants and gas stations.