The Nokia Lumia 1020 is a smartphone developed by Nokia, first unveiled on 11 July 2013 at a Nokia event in New York. It runs Windows Phone 8, but is also Windows Phone 8.1 ready. It contains Nokia's PureView technology, a pixel oversampling technique that reduces an image taken at full resolution into a lower resolution picture, thus achieving higher definition and light sensitivity, and enables lossless digital zoom. It improves on its predecessor, the Nokia 808, by coupling a 41-megapixel 2/3-inch BSI sensor with optical image stabilization (OIS) and a high resolution f/2.2 all-aspherical 1-group Carl Zeiss lens. It was considered to be the most advanced cameraphone when released in September 2013.