Over the past few months, we've made it our mission to dig up the best free smartphone applications available. A ways back, we profiled a half dozen free BlackBerry downloads. Then we touted seven great Windows Mobile applications you can pick up without dropping a dime. But we knew those wouldn't be enough for you, so we kept on searching and found another six free can't-miss BlackBerry apps—we even asked a few Research In Motion (RIM) executives for their third-party software faves.

This time around, we went the open source route, and found five great—and free—BlackBerry apps we know you'll like. You'll find a secure password keeper; a Bloglines-based RSS reader; software that brings "push" mail and over-the-air (OTA) sync to a variety of enterprise and consumer Web mail and PIM services; a cool GPS location-logging utility; and a set of tools to give you more control over your BlackBerry's backlight and messaging options.

KeePass for BlackBerry—The Open Source Password Keeper

Passwords for corporate systems, passwords for Web mail accounts, passwords for sites, online forums and users group. The list just goes on and on. Today's tech-savvy businessperson has more passwords than important things to do and meetings to attend. And as any security conscious user knows, it's good practice not to reuse the same password for different accounts. From a security standpoint, the more passwords, the better.

KeePass Password Keeper

That's where KeePass for BlackBerry comes in. The application is a mobile sibling of the popular KeePass Password Safe for desktop computers, and it's an open source alternative to the default RIM Password Keeper that comes pre-installed on newer BlackBerry devices. The BlackBerry-specific version was written from scratch to take advantage of unique RIM users interface feature, and it's locked with one master password so you need only remember a single login for access to all your passwords. The application databases are encrypted using the AES and Twofish algorithms for added security. And because it's open source, you can peek at the full source code to, say, check if the encryption algorithms are correctly implemented.

KeePass for BlackBerry is available for OTA download and its source code can be found here. (Note: BlackBerry handheld OS 4.2.1 or higher is required for access to full KeePass for BlackBerry functionality.)