Covert Antenna Systems (CAS) in conjunction with The University of Nottingham, are developing a clip-on antenna system with coupler for mobile phones. This system will provide enhanced GNSS reception, enabling improved position estimation from mobile phones. In addition we will also take advantage of the opening of the Android GNSS interface to access the raw GNSS data to enable developers to enhance the positional estimate, potentially providing near survey grade accuracy. The project has been termed MPOE (Mobile Phone GNSS Observation Enhancer). MPOE will enable many suppliers to create mobile phone applications (Apps) with enhanced accuracy navigation. This should allow many more utilities, which would currently require a high accuracy GNSS receiver to operate using a mobile phone.