What is more annoying than doing that calculation above me? Seriously! I have x amount of protein in ug what is my molar concentration? You are probably smarter than me, but I have a tendency to lose a decimal place or two. This week I said "wow, there should be an app for that". And there is. Of course.
Promega has a free BioMath calculator that will do this one for you, among other things. (Lots of DNA calculations and dilutions, but this is what I downloaded it for!) It is available for both Android and Apple.
You can read more about it here. A big thanks to the talented team at Protea for pointing this one out to me!