Demod: SDR Receiver

Demod turns your Android phone into a software-defined radio receiver. Connect to an SDR server on your own network or anywhere on the internet and explore the airwaves — from shortwave broadcasts and ham radio to aircraft, marine, and FM.

Demod is a client for the most common SDR servers:
• KiwiSDR — HF web receivers
• OpenWebRX — web SDRs (HF, VHF and UHF)
• SpyServer — for Airspy and RTL-SDR
• rtl_tcp — for RTL-SDR dongles

There's no hardware to plug into your phone. Point Demod at a server you run (a Raspberry Pi, PC, or Mac with an SDR dongle), or browse hundreds of public servers around the world and start listening in seconds.

FEATURES
• Real-time waterfall and spectrum display
• Pinch to zoom, drag to tune
• AM, NFM, WFM, USB, LSB, and CW demodulation
• Decode CW (Morse), RTTY, PSK31, and FT8 on-screen
• Record what you hear to M4A files
• Live Text: on-device speech-to-text captions of what you're listening to (downloadable Vosk language models), with on-device translation of the captions and a full-screen transcript reader
• Identify: one-tap "what is this signal?" — measures the signal on-device and matches it against a built-in band plan
• Scanner: scan your memories or a band range
• Spectral noise reduction and a mains-hum notch that picks 50 or 60 Hz for your region
• Browse public KiwiSDR, OpenWebRX and SpyServer receivers worldwide — list or map view, sorted by reachability
• Save and recall favorite frequencies — import and export as CSV
• Share a tuned station as a link that opens in Demod on iOS or Android
• Direct-sampling and upconverter support for HF
• Background playback with media notification and headset controls
• Adjustable bandwidth, gain, squelch, and display layouts

PRIVACY
No accounts, no ads, no analytics from the developer. Recording, transcription, translation, signal identification and decoding run on your device. Demod connects directly to the radio servers you choose. Translation uses Google ML Kit, whose SDK contacts Google for models and diagnostics; see the privacy policy for details.

Built for radio hobbyists, shortwave listeners, scanner enthusiasts, and ham operators who want a fast, native receiver in their pocket.

Note: Demod is a receiver client and requires an SDR server to connect to. You can use a server you run yourself or one of the many free public servers listed in the app.