20. A method of estimating a reader's reading position in an electronic text comprising: using a first means to locate a first reading position of a reader at a first time; detecting a reading scan rate of the reader by tracking a reader's eye movements using an eye tracker to detect at least one of a predetermined type of eye movements, the reading scan rate based on the detected type of eye movements and based on a timer, the reading scan rate being a value indicative of a number of eye movements per unit of time without requiring detection of an exact position of a reader's gaze within the electronic text; using the detected reading scan rate to estimate a reading speed of the reader based on supplementary scan rate data relating to the electronic text and/or reader that is indicative of an actual or average quantity of electronic text per type of detected eye movement; and estimating a reader's reading position at a second time based on an incremental time from the first time, the estimated reading speed and the first reading position.
21. The method according to claim 20 wherein the first reading position is determined from any of the following: a page turn signal, a touch input on a touch screen display showing the electronic text, and/or or a navigational input for traversing electronic text.