My KiwiSDR: this can receive from 0 to 30MHz and has a variety of decoders and modes built in. It has four receivers of which three are available to use if they are not already in use. The fourth is reserved for me!
Currently it is connected to one of two YouLoop antennas in the loft. The antenna does not have any amplification and, while it works really well with the Airspy HF+ Discovery is not not optimal for the KiwiSDR. But it is all I have for now. I am still experimenting but so far the only other option is a CCW HF loop which picks up far too much noise and needs attenuation as well... not a fault of the antenna, just that it is in the loft.Also the GPS seems a little insensitive compared to my other kit. I have an external GPS antenna to install which should help.
Information about the KiwiSDR can be found at http://kiwisdr.com/ and there is a list of public SDR receivers at http://kiwisdr.com/.public/ and a map at https://rx.skywavelinux.com/.
Note: the KiwiSDR does not support encrypted connections and so is only http: not https:. Some browsers will issue a warning and some may even refuse to connect at all. I do not know when or even if this will be resolved in the future.
And of course... my Blog