A method of determining a concentration of an
analyte in a bodily fluid is disclosed. The method comprises using a
mobile device (112) having a camera (114). Further, the method comprises capturing at least one image of at least a part of an
optical test strip (124) having a test field (126) by using the camera (114). The method further comprises determining at least one
analyte concentration value from
color formation of the test field (126), wherein the method comprises: i) providing, in the
mobile device (112), at least one correlation for transforming
color formation of the test field (126) into the
analyte concentration value; ii) providing, in the
mobile device (112), at least one item of clearance information, the at least one item of clearance information indicating a level of confidence for the correlation; and iii) if the item of clearance information indicates a sufficient level of confidence for the correlation, providing, by the mobile device (112), indication to a user that the capturing of the at least one image does not require using the color
reference card (128). Further, a method of controlling analytical measurements, a mobile device (112), a
system (110) for controlling analytical measurements and computer programs for performing and / or controlling analytical measurements are disclosed.