Digital Light & Color

I found the app very useful.

Suggestions for usability in DoF mode:

• Inputs are currently located on the left and on the right of the screen. Inputs include lens focal distance, aperture and acceptable blur. Suggestion : place all input sliders to the left. That is, move acceptable blur to the left.
• The focusing distance slider looks and operates very differently from the aperture and focal length sliders. Suggestion : swap the focusing distance scale and the blur scale associated with red far and near levels such that the focusing distance input appears next to the other inputs.
• The focusing distance scale is not directly swipeable. The viewable window on the focusing distance scale adjusts up or down as a reaction to user setting the focusing distance. Suggestion : allow user to move the focusing distance scale up or down to allow different areas to be displayed in the visible window. This will enable quicker selection of an off-window distance by user.
• There is no numeric display of the hyperfocal distance. The near distance is displayed above the acceptable blur scale and the far distance is displayed above the focusing distance scale. Suggestion : display numeric values of hyperfocal distance, far distance, actual focusing distance and near distance in a single column. Use blue for hyperfocal ; white for actual focusing ; red for far and near distances

I believe the 3rd bullet would be the most important for me. All are good suggestions.