Rather than wait around for your software to notify you of updates (let's face it, a lot of applications never will), these five handy tools keep an eye on your apps, alert you when an update's available, and streamline the updating process.
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FileHippo Update Checker (Windows, Free)
FileHippo.com is a software download site that hosts tons of both freeware and shareware, so the FileHippo Update Checker is a natural extension of their web site—only better. The lightweight application (the download is 155kb) scans your computer for installed apps in seconds, compares your installed version with the FileHippo.com database to check for new releases, then lists all detected updates in a list in your browser along with links to download your updates. FileHippo Update Checker is a free download for Windows only.
Synaptic/APT (Linux, Free)
The Advanced Packaging Tool, a.k.a. APT, is a free tool built into most Linux distributions and many variants that handles the installation, removal and updating of software packages. APT is a tool that went a long way toward making Linux a bit friendlier to the masses who aren't comfortable installing or compiling software packages on Linux, but it runs from the command line, so it's still not all that friendly to folks joining Linux from the Windows or Mac worlds. That's where Synaptic comes in. Synaptic is a graphical front end to APT that makes the tool wildly more user-friendly, and—yes—it handles checking for and updating software with aplomb. (Folks using Ubunutu, take note: Synaptic will be replaced by the Ubuntu Software Center—another APT-powered update tool—in April of 2010.)
AppFresh (Mac OS X, Free)
AppFresh is an automated update checker for Mac OS X. The tool scans your computer for installed software and checks for new versions against the database at web site i use this. Aside from also encompassing the functionality of Apple's built-in Software Update utility (if you install this, you won't need to run that), the app filters your updates and installed applications in a number of useful ways, and provides descriptions of each tool in a handy info panel along with release notes. Perhaps most impressive, AppFresh can automate the update process for many of the apps so you don't have to go through the tedious process of downloading and installing every single update by hand. AppFresh is free (though currently in a "Development Preview", which could mean it will eventually cost money), Mac OS X only.
Update Notifier (Windows, Free)
Update Notifier is a small, portable software update utility that quickly scans your installed applications and lists your available updates in a small window, complete with links to sites where you can download updates. The application includes options to filter all your installed applications, updates only, major updates (2.0 to 3.0), minor updates (2.0 to 2.1), and build updates (2.0.0 to 2.0.1). If you register for an account at the CleanSofts.org web site (the companion site to the application), you can also set up a watch list and let the site email you whenever updates to apps on your watch list are available. Update Notifier is freeware, Windows only. It's also portable, which could come in handy next time you're heading to your after-hours job moonlighting as your family's IT person. (Original post)
Secunia PSI (Windows, Free)
Secunia Personal Software Inspector takes a bit more of a doomsday—i.e., security-focused—approach with software update. When you run your first scan after installing Secunia, you'll be presented with a list of insecure apps that have available updates, "end-of-life" apps that are no longer being supported by the developer, and patched apps that have the latest security updates. It's not the most user-friendly of the bunch, but the interface is packed with information and tools for making sure your installed software is running the latest and greatest security updates. Secunia PSI is freeware, works with Windows. (Original post)
Surprised your favourite didn't make the list, or just want to share what makes your software update tool of choice so great? Let's hear it in the comments.