RTL SDR Software Defined Radio running on Android phones and tablets running Ice Cream Sandwich.
Take a phone or tablet running Android Ice Cream Sandwich, a USB cable wired for OTG, and a $20 USB TV Stick, and you have a touch screen radio scanner capable of tuning anywhere from 52-2200Mhz.
From their website:
“Turns your mobile phone or tablet into a cheap and portable software defined radio scanner. Allows you to listen to live on air FM radio stations, weather reports, police, fire department and emergency stations, taxi traffic, airplane communications, audio of analogue TV broadcasts, HAM radio amateurs, digital broadcasts and many more! Depending on the hardware used, its radio frequency coverage could span between 50 MHz and 2.2 GHz. It currently demodulates WFM, AM, NFM, USB, LSB, DSB, CWU and CLW signals.
You can get a compatible USB receiver for under $20 online from eBay. Just plug in your rtl-sdr compatible USB DVB-T tuner into your Android device using a USB OTG Cable and turn on SDR Touch. For list of supported Realtek RTL2832U based dongles, please see the end of the description. Those features are supported via a driver that you will need to download from Google Play.”