Until now, you couldn't get external access to the GPS inside your iPhone or iPad, but now with GPS2IP you can stream the information in realtime to solve your requirements.
Each device running GPS2IP can send a unique identifier, so that if you have multiple devices you can determine which device is sending what messages.
If your device dies or you turn it off when it was running, GPS2IP now automatically resumes sending the location.
GPS 2 IP can run when the iPhone sleeps to support constant location reporting, but be aware that continued use of the GPS when running in the background can dramatically decrease battery life.
BEWARE - GPS2IP is *not* able to be used for the Apple turn-by-turn navigation app, or Google Maps, or most car navigation programs.
GPS2IP now can be configured to restart automatically after your iOS device restarts, so you'll always keep track of your position.
Apart from navigation software, other methods for connection include telnet or netcat, or many terminal programs.
Alternatively, you can also push the NMEA data to any online server, using either TCP or UDP and process the information however you want.
GPS2IP can also be configured to output data at a selectable frequency (for example once every minute).
The iPhone becomes a GPS server, and to get the information, you just connect to your iPhone using either wifi or Bluetooth LE.
It is designed for enthusiasts, or more sophisticated navigation software that can use an external wireless GPS unit.
Some navigation software such as MacEnc can read from an IP address natively.
One non-standard message that GPS2IP transmits that is very useful for sailing is $PASHR.
Beware that this will decrease battery life - we recommend keeping it charging if possible.
