"VIDEGRO's Ships is a free Android application which allows you to receive AIS information directly from ships in your neighbourhood using a cheap DVB-T-DAB-FM / RTL-SDR receiver. You need to have an OTG capable Android device and a DVB-T-DAB-FM / RTL-SDR receiver, otherwise this application is useless. Search eBay / DealeXtreme for 'DVB-T-DAB-FM' to obtain one.