DroidNavtex decodes NAVTEX messages from your receiver through your phones/tablets microphone or through a connected interface. Special audio filters even decode very weak signals through the microphone and make DroidNavtex a very affordable alternative to high priced decoders. NAVTEX broadcasts worldwide on 518 kHz and 490 kHz using a data mode called SITOR-B (amateur radio (Ham Radio) operators might recognize it as AMTOR). Sharp filters and a sophisticated forward error correction algorithm makes decoding of very weak signals possible. Get your copy of DroidNavtex today, and never be without up to date marine weather information and marine warnings again.. You need to have a receiver which can receive 518KHz or 490KHz SSB to use this app!! An “Auto mode” finds the frequency and the sideband of the Navtex signal automatically. With “Auto mode” turned off the frequency and sideband can be adjusted manually. A built-in database stores the received messages which can then be filtered, sorted and shared. Messages can be deleted individually, in groups or by age. To save battery power 7 timers can be set to start DroidNavtex at a given time to decode messages. All timers can be set in local time or UTC. Great to use on all seagoing sail and power vessels, sailboats, power boats, fishing boats and commercial vessels. You can find a detailed user guide at www.droidnavtex.com I realize that the 15 minutes which Google allows is not enough for testing DroidNavtex. If you are not happy with DroidNavtex please email us at info@wolphi.com to request a refund.