Zoll - mm is a free Android app developed by Detlef Lorenz that helps users convert millimeters to inches and vice versa. The app also provides a table of inch measurements in decimal fractions. While it may not be perfect, it is completely free and does not contain any advertisements.

The app's interface is straightforward and easy to use. Users simply input the measurement they want to convert and select the desired unit of measurement. The app then quickly provides the converted measurement. The table of inch measurements is also easily accessible and provides a helpful reference for users who frequently work with these measurements.