I would only use Hydra as a last resort for for low-light shots and zoomed in shots. Its use is very limited because it requires a still scene, a steady hand/tripod, and a long exposure time.
HDR mode: In my tests, the results are inconsistent. Sometimes they look decent, and sometimes they look unrealistic. The iOS Camera app produces the best HDR photos in my opinion.
Video-HDR mode: I dont notice a difference on between videos shot in this mode and videos shot in the native Camera app.
Lo-light mode: Dramatically reduces the amount of noise/grain in low-lighting conditions. I love it!
Zoom mode: It really does work. Im actually impressed with how much clearer the zoomed-in photo is. There is a dramatic difference, especially if theres text in the photo. However, you cant set the exposure in this mode.
Hi-res mode: It does produce a higher resolution photo, but it isnt worth the requirements of a perfectly still scene and the long exposure time.
The option to save the uncompressed photo is a great feature because you can really see the difference between a normal photo and a Hydra photo.
Feature Requests:
* The ability to set the exposure (ISO) in zoom mode.
David_Burns_Red about Hydra › Amazing Photography