Where can Raspberry Pi be used as a crowdsourcer?

Question

Raspberry Pi

There is a Raspberry Pi and an RTL SDR receiver. I would like to apply this in some kind of crowdsourcing project, where people put autonomous stations at home that receive something and send data to the server.
Recommend these projects.
I myself know about ADS-B signal receivers and sending them to flightradar. I tried to do, everything worked, but I want something more important. Because in Novosibirsk, even without me, planes are perfectly tracked.
I also know a people's map, where you can show the values ​​​​of temperature, humidity. But the value of this data is also questionable.
Can make a LoRa gateway? Or I also read that people receive a signal from amateur satellites and send it to a central server, thereby increasing the coverage map of this satellite.