OpenWebRX is described as 'remote spectrum monitoring solution with the following features: - libcsdr based demodulators (AM/FM/SSB), - filters with changeable bandwidth, BFO and PBS, - waterfall display that can be shifted back in time, - uses HTML5 features like WebSocket, Web'. There are seven alternatives to OpenWebRX for Linux, Mac, Windows and Android. The best alternative is CubicSDR, which is both free and Open Source. Other great apps like OpenWebRX are Gqrx (Free, Open Source), SDR# (Free), SDRangel (Free, Open Source) and inspectrum (Free, Open Source).
Gqrx is a software defined radio receiver powered by the GNU Radio SDR framework and the Qt graphical toolkit. It supports many of the SDR hardware available, including Funcube Dongles, rtl-sdr, HackRF and USRP devices.
SDR# (SDRSharp) is a popular, simple, fast and extensible Software Defined Radio program written from scratch in C# to experiment new Digital Signal Processing techniques and push the Microsoft .NET Framework to its limits.
A graphical application for showing the Fast Fourier Transformation (FFT) as graph and waterfall diagram of the radio spectrum retrieved by Software Defined Radio (SDR) devices supported by GrOsmoSDR. Plugins enable demodulating a selected signal.