A capacitive touch sensor comprises a plurality of electrodes on a substrate, and a position of a finger touching the sensor is determined by monitoring output signal changes caused by changes in capacitance caused by the present of the finger over or near the electrodes. The disclosure provides a capacitive touch sensor apparatus comprising a substrate and a plurality of touch sensor electrodes arranged on the substrate. Each of the electrodes comprises a respective primary electrode strip and a respective one or more electrode strip branches extending from the primary electrode strip.