A few camera apps allow you to select ISO. Android provides an ISO mode called HJR, but almost nobody knows what it is, and so far none of the camera apps I've looked at has it quite right.
HJR is Google's "Hand Jitter Reduction." It's pretty simple: it's an auto-ISO mode that puts its priority on faster shutter speed rather than lower ISO.
Vignette offers the option, but it's currently labeled "HDR" rather than HJR.
Camera360 Ultimate offers the option, but if I choose it, the app locks up after I take a picture. I not only have to force-close the app, I also have to restart my phone to get C360 working again. By the way, C360 doesn't store exposure information in the EXIF,
Retro Camera offers the option, but Retro doesn't put the exposure information into the captured EXIF file, so I can't tell for sure if it's working or not.
Oddly, Android's own Camera app doesn't offer the option. The only ISO settings it offers are low ones, apparently intended for those users who want to force a lower ISO setting.
By the way, Camera FV-5 doesn't offer the HJR option, but FV-5's ISO setting is a placebo anyway. FV-5 always uses auto-ISO, no matter what setting I choose. I'm looking at the Lite version, but the documentation says that the Lite version is "fully functional" except for resolution, so I expect that the full paid-for FV-5 also doesn't do anything with the ISO setting.
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