This calculator is alpha at best. I plan on hopefully fine tuning and adding more to this very soon.
What this does to date is calculate the memory you will require for your Lync FE servers to properly scale for Lync Mobility.
It requires you to enter your planned user bases (IOS/Windows Phone or Android/Nokia) and will output data based on the Microsoft Planning Formulas.
I do not take any credit for these formulas, I am simply putting them in a spreadsheet for easy access.
Let me know your thoughts in the comments, I will continue to update and hopefully make this a valuable tool!