Be sure to have google open to convert metric to imperial or to whatever (i dont know what a serving of 1 person is!) Be sure to have a calculator too for all the math you need to do. Also be sure you have your charger because this app is a battery drain...especially the bar code reader which you use to read the bar code and enter it manually. The nutritional information is inaccurate 95% of the time so be sure to enter each item manually. This app will make you a couch potato.