Android: Grid Size File Manager quickly analyzes your Android device's SD card to show you a visual representation of what's taking up the most space.
The app, which costs $0.93 for the ad-free version, does a pretty decent job of quickly analysing and displaying the contents of your /sdcard directory in a full-screen grid of colours.
The visual representation is clean and easy on the eyes, but items with smaller file sizes are too small to have labels. Unlike similar desktop software I've used before, though, that's quickly remedied with a simple pinch to zoom.
It also doubles as a regular file manager. Tapping any folder or file's coloured block will open it, while long-pressing will bring up file-management options (like cut, copy, paste, or delete).
The app is very simple, and has no settings or options to speak of. There is a secondary view available, though. It loses the multicolored GridView and replaces it with plain lines of text, and definitely helps with using the app as a file manager.
Grid Size File Manager costs $0.93 for the ad-free version, with an ad-supported version available free of cost. It requires Android 2.0 or higher, and can be downloaded at the Android Market.