OpenWebRX[1] is a similar open-source sdr frontend, KiwiSDR is based on a slightly older version before it was picked up by a new maintainer. It's really nice being able to use the digital protocol decoding baked-in to it. Usually in the VHF ham band you can park it on the default "PACKET" bookmark and look at all the APRS traffic going around, and if the person running it has added the VHF/UHF buisness bands in that particular area the POCSAG decoder works great. Same for the digi protocols like FT8 et al. on the HF ham bands.
There's also another online directory[2] of mostly all available KiwiSDR, OpenWebRX, and WebSDR receivers with a cool map view.
I ran an OpenWebRX node for a good while before taking it down with the intention of upgrading it to an SDR with a wider bandwidth and a few multi-band antennas for better performance, might get around to finishing that up now.
There's also another online directory[2] of mostly all available KiwiSDR, OpenWebRX, and WebSDR receivers with a cool map view.
I ran an OpenWebRX node for a good while before taking it down with the intention of upgrading it to an SDR with a wider bandwidth and a few multi-band antennas for better performance, might get around to finishing that up now.
[1] https://www.openwebrx.de/
[2] https://www.receiverbook.de/