GPS accurracy correction for Android App

Project EGNOS-Module: In an existing Android App a new module is to be programmed, so that the GPS signal gets more accurate. For this task, the EGNOS-correction (euopean free WAAS service) should be utilized. Since the internal GPS sensors cannot deliver neither this signal nor a raw GPS-signal, we need an additional bluetooth GPS device ("GPS-mouse"). The EGNOS correction data is a live correction signal, which is available both through satellite signal and also over the internet as a live-correction stream. The GPS-mouse can also receive the EGNOS-signal from space, and since that is free, internet depending on the customers data plan not, the signal from space source is preffered. The module consists of the following three components: 1. A raw signal needs to be made available to the app. a) Selection of the right bluetooth device (should be a rather cheap one, maybe $70-100). b) The bluetooth interface will be implemented. For that probably a raw signal is needed (or nmea?). 2. The technical/mathematical implementation of the GPS correction. Those formulas are out there on the web. input: (raw-GPS data, EGNOS correction data) -> output: EGNOS-corrected GPS 3. A setup, which can handle the module. a) Switch EGNOS, bluetooth device correction on/off. b) EGNOS over internet/satellite-only. E.g. the priority should be like this: test 1: Is GPS-mouse available? no -> take internal GPS. yes -> test 2: EGNOS from satellite available? yes -> take raw-GPS, corrected with EGNOS from satellite. no -> test 3: is internet available and is EGNOS over internet allowed/switched on by the user? yes -> take raw-GPS and correct it with EGNOS from internet. no -> just take the raw-GPS signal from the GPS-mouse. Since smartphones are used out there in the real world, the above priority list can change during one session of a user with our app. At any given moment, the most accurate and cost efficient solution should be presented to the user. More precisely: suddenly the EGNOS-correction is not available through space signal anymore, then we try internet EGNOS, or may be the bluetooth connection breaks down all together due to low battery and we have to rely on the (less accurate) internal GPS etc. Please make an offer on how long the programming of this module will take and how much it will cost, could be hourly or budget.