Preprints are manuscripts made publicly available before they have been submitted for formal peer review and publication. They might contain new research findings or data. Preprints can be a draft or final version of an author's research but must not have been accepted for publication at the time of submission.
A method of calculating screen to face distance is presented. The method relies on average distance between the user’s eyes (pupillary distance) and does not require calibration. The algorithm is implemented as an Android application using face detection technologies provided by Android.