Sharpshooter is a nice tool for users who take lots of screenshots. Mac OS X's screenshot-taking app is a wonderful tool. It has been a blessing for me, and many people that I know. But it is not easy to customize the way this app assigns names to files and the formats that it uses. I was able to change them using a third-party app, but I can't remember what it was called. Sharpshooter is a different type of solution to that problem. It installs an agent that monitors your Mac. When you take a screenshot, it can carry out a few different actions. For example, it can present it to you, so that you can rename it, change its format and the location where it will be saved. If you don't want to add changes manually, you can set the application to automatically change any of those attributes for every screenshot that you take.
The reason why Sharpshooter was made was to address the issue of not recognizing screenshots by its filename. Having the app ask you to rename all the screenshots that you take helps with this. In my case, it wouldn't really help because I take tons of screenshots every day, and I'd be losing a ton of time doing this manually. The automatic features are tempting, though.