Pretty great

HDR software can be complicated and expensive, and it requires 3 to 5 identical shots with different exposures This app makes it super easy and free; it also does a great job of simulating HDR on single images using tone mapping by itself. On my iMac it imports JPGs and RAW files by drag and drop, no problem, and works like a charm.
Note that HDR is only useful for certain types of shots. This software does the simplest possible HDR, but does it super fast and easy, and still allows you to vary the strength of the effect. If your camera cant be set to auto-bracket exposures, and if you cant at least mount it on a bean bag or mini-tripod with a self timer, you wont enjoy the multiple-exposure feature quite as much, but even then, you can align the images by hand.
All in all, an awesome free app. I will be checking out the Pro version...

iamasiam about HDRtist