A METHOD OF CONTROLLING AUTO-EXPOSURE SETTINGS OF A MOBILE DEVICE HAVING A CAMERA

A method of controlling auto-exposure settings of a mobile device having at least one camera is disclosed. The method comprisesa) providing a color reference card (110) and an optical test strip (118) having a test field (120) having a sample applied thereto,o wherein the color reference card (110) comprises a plurality of different color reference fields (112) having known reference color values and one or more gray background fields (114) having defined gray values,b) setting an exposure metering area and determining auto-exposure settings based on the scene (126) in the set exposure metering area;o wherein the scene (126) in the set exposure metering area comprises at least part of the reagent test field (120) of the optical test strip (118) having the sample applied thereto, and at least part of the plurality of different color reference fields (112) and at least part of the one or more gray background fields (114) of the color reference card (110),c) capturing, by using the camera (120), at least one image comprising the scene (126) of step b)o wherein the determined auto-exposure settings of step b) are used.A method of determining the concentration of an analyte in a sample by using a mobile device is also disclosed.