This app calculates the fractional excretion of sodium based on the serum and urine sodium and creatinine values. Based on the FENa value the associated etiology of pre-renal, intrinsic and post-renal disease can be deduced. A link to the FENa Wikipedia page is included. A custom keyboard makes it quite easy to enter the measurements on serum and urine. No need to press a calculate button, the FENa is calculated real-time as you type. Change the unit of measure by pressings the unit of measure b