Fix the description!
Old Johan, Motu007 may have said that because of the confusingly worded description; actually that's what I was looking for as well.
Just because one measurement is a volume and the other is a weight doesn't mean you can't convert between the two; provided you know the volume and weight of a unit of an ingredient, you can of course calculate it to at least a general degree of accuracy, and there are websites that do this and/or have tables with these measurements listed. Unfortunately this app does not.
It does look better than the very not free competitor though (although its icon does not), and seems to execute the functions advertised smoothly enough.
But... The wording of the description was a cause for disappointment on my end... I'd recommend revising it (or better yet, adding weight-volume conversion!).