SDR Software (Host)

The host-side application that turns IQ samples into audio, waterfalls, and decoded text. A single SDR works with all of these — driver support is unified by SDR Drivers & Frameworks. For protocol-specific decoders (ADS-B, AIS, P25, FT8) see the dedicated decoder pages; this is the general-purpose receiver UI layer.

General-purpose desktop receivers

• ★ SDR++ — modern, cross-platform (Windows / Linux / macOS / Android), GPU-accelerated waterfall, plugin architecture, supports nearly every SDR via SoapySDR + native modules. The 2026 default — replaced SDR# in most workflows. GPLv3.
  • https://github.com/AlexandreRouma/SDRPlusPlus
• ★ SDRangel — feature-rich GUI; dozens of demodulators built in (FT8, AIS, ADS-B, DAB, DVB-S, AM/FM/SSB, APT, M17, NAVTEX, satellite trackers). Ugly Qt UI but unbeatable feature surface. GPLv3.
  • https://github.com/f4exb/sdrangel
• ★ GQRX — clean Qt receiver for Linux / macOS; built on GNU Radio; the FOSS gold-standard simple receiver. Limited to one band/tuner at a time but pleasant to use. BSD-3.
  • https://gqrx.dk
• CubicSDR — cross-platform C++ receiver; multi-channel demodulation; less actively developed than SDR++ but still works. MPL-2.
• HDSDR — Windows; freeware, closed source; HF-DXer-favorite UI. Long-standing.
• SDR# / SDRSharp — Windows-only; freeware, closed source. The historical default; well-loved, plugin ecosystem (SpyServer streaming, IF Recorder, frequency manager). Still useful for SDRplay / Airspy on Windows but SDR++ and SDRangel are catching/passing it. License caveat: not OSS, no Linux build, plugins are mostly third-party freeware.
  • https://airspy.com/download
• SDRuno — SDRplay's official receiver; closed Windows app; integrates well with their hardware but most users prefer SDR++ via the SDRplay API.

Web-based / remote receivers

• ★ OpenWebRX+ — the web-SDR. Run it on a Pi with an SDR and share your radio with the world over a browser. Multi-user, waterfall, all the standard digital decoders (FT8, FT4, WSPR, FAX, SSTV, RTTY, ADS-B). Continuation of OpenWebRX after 2023 fork; the active 2026 maintenance. AGPLv3.
  • https://github.com/luarvique/openwebrx
• OpenWebRX (original) — the upstream; less active but still used.
• KiwiSDR / KiwiSDR2 — purpose-built HF web-SDR hardware + software stack; the websdr.org public stations are mostly KiwiSDRs. Hardware ~$300; the software is closed-but-free for the box.
• WebSDR (PA3FWM) — original Java-applet web-SDR software; nostalgic; many public listening posts still run it. Closed source.
• SpyServer — Airspy's streaming-server protocol; receive a remote SDR over the internet from SDR# / SDR++. Closed but free.

Mobile

• SDR Touch (Android) — pay app; works with USB OTG + RTL-SDR.
• ★ SDR++ for Android — same SDR++ codebase ported; FOSS; plug an RTL-SDR into your phone via USB-C OTG.
• RFAnalyzer (Android) — basic FOSS waterfall.

Specialty / niche

• CubicSDR + cubicsdr-modules — for users who want a different multi-channel UI.
• DSDPlus / DSDPlus Fastlane — Windows; closed; paid Fastlane variant adds modern voice codec support; the de-facto P25 / DMR / NXDN voice decoder if SDRTrunk's not enough. See Trunked & Public Safety.
• fldigi — see Ham Digital Modes; fldigi is digital-mode-focused, not a general receiver.

Practical guidance

• AGC off, manual gain. SDRs all have AGC by default; manual gain is almost always better — especially with a strong nearby pager / FM broadcast.
• Use the IF / spectrum view. Most decoding problems are level problems. Watching the IF spectrum scroll past the waterfall tells you immediately whether you're seeing the signal.
• SpyServer / rtl_tcp / SoapyRemote — share an SDR over the network so the box-with-the-antenna isn't the box-with-the-screen. Easy way to put the SDR in the attic.
• Recording IQ. Every app here can dump raw IQ samples (or .wav IQ); replay later in any other tool. Critical for analysis, mostly missed by beginners.
• Plugin ecosystems. SDR# and SDRangel have the deepest. SDR++ is catching up via its module system.

License / pricing notes

• ★ FOSS: SDR++, SDRangel, GQRX, CubicSDR, OpenWebRX+, fldigi.
• Closed-but-free: SDR#, SDRuno, HDSDR, SpyServer.
• Paid: DSDPlus Fastlane ($100), SDR Touch ($10), SDR4Space (lab pricing).
• Driver dependency: every receiver here pulls SDRs in via SoapySDR or vendor APIs. See SDR Drivers & Frameworks.

Pick this if…

• Default 2026 desktop SDR receiver: SDR++.
• Maximum demodulator count: SDRangel.
• Clean, minimal Linux receiver: GQRX.
• Share your SDR on a webpage: OpenWebRX+.
• Windows-only, closed-but-loved, plugin ecosystem: SDR#.
• Decode P25 / DMR voice (paid): DSDPlus Fastlane (and see Trunked).
• Phone-as-SDR-receiver: SDR++ on Android with USB OTG.