ProCamera

ProCamera gives you a fully functional stills camera application optimized for Samsung devices with Qualcomm processors. Created with picture quality and minimal processing in mind.

For phones with Android 6+ Marshmallow, please see note below.

Most phones do not yet support Google's Camera2 API, and thus can only save compressed JPEG files. In addition, most devices use artificial edge-sharpening and noise reduction algorithms which further reduce the quality the resulting pictures by adding halos around edges and an oil painting appearance to low contrast areas.
This app disabled all artificial enhancements. JPEG quality is set to maximum, artificial sharpening/edge enhancements are disabled, and noise reduction is also disabled (but can be enabled in the app) thus retaining a more natural film grain.

•  Live ISO and Exposure Time displayed (device dependent).
•  Selectable Histogram modes: Luma, RGB or both.
•  Selectable Metering Modes (Matrix, Center Weighed, Spot).
•  Selectable ISO modes.
•  Selectable Sensor Resolutions.
•  Adjustable Exposure (not supported in all ISO modes, device dependent).
•  Defeatable built-in sensor noise-reduction.
•  Defeatable location services and tagging.
•  Selectable Focus modes: Continuous AutoFocus or Touch to Focus.
•  Orientation sensor updates Exif tag, can be locked.
•  Shake detection.
•  GPS data added to Exif tag (can be disabled).

No Twitter, Google+ or facebook integration.
No fisheye, cartoon or sepia filters.

•  Due to the use of undocumented system calls, device compatibility CANNOT be guaranteed. The application may crash and/or some features me have no effect.

Please try "ProCamera Lite" for free before buying:
https://play.google.com/store/apps/details?id=com.breakpoint.procameralite

The app has been tested successfully on Samsung devices running ICS 4.0.2 and up. It may also work on a wider range of devices using CyanogenMod 9 and up.

 Pictures taken without noise reduction enabled may require retouching using an external app, especially with higher ISO settings. Processing on a PC can achieve far better results than the limited processing used in smartphones and tablets.