Freelancer:
Urtin
Unit Converter for Android Wear
Here is a design for your app, it's designed on Lollipop Material design, and it has the functions that you mentioned in the brief. I hope you like it. If you have any Logo that you want to integrate in the design please send it to me, and also, if there is any changes you want I can provide it for you. The files are in .ai format and there are all layered.