Powerful, handy, versatile... – MaxCurve Review

When I need quick color & value correction on my iPhone & iPad, this is my go-to. Curves are extremely powerful & flexible editing paradigms, and they're implemented really well here. Plus, this app's inclusion of (basic) non-curve HDR, grain, sharpness, layering, etc really rounds it out. While curves can also get tricky when you micromanage them with lots of points, MaxCurve's undo history, presets, (and the actual curves interface) keeps it easy to manage and re-think your edits on the fly. Highly recommended.
Review by ruskoberger.com on MaxCurve.