<P> Most camera phones have a digital zoom feature . A few have optical zoom . An external camera can be added, coupled wirelessly to the phone by Wi - Fi . They are compatible with most smartphones . </P> <P> Images are usually saved in the JPEG file format, except for some high - end camera phones which have also RAW feature and the Android 5.0 Lollipop has facility of it . Windows Phones can be configured to operate as a camera even if the phone is asleep . An external flash can be employed, to improve performance . </P> <P> Phones usually store pictures and video in a directory called / DCIM in the internal memory . Some can store this media in external memory (Secure digital card or USB on the go pen drive). </P> <P> Camera phones can share pictures almost instantly and automatically via a sharing infrastructure integrated with the carrier network . Early developers including Philippe Kahn envisioned a technology that would enable service providers to "collect a fee every time anyone snaps a photo". The resulting technologies, Multimedia Messaging Service and Sha - Mail, were developed parallel to and in competition to open Internet - based mobile communication provided by GPRS and later 3G networks . </P>

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