SDR++ seems to work the best with my RSP1A, I still have to use a closed source driver that hasn’t been updated since Dec 2019. At least the driver works fairly well, but sometimes it locks up and the sdrplay service has to be restarted.
The Android driver, on the other hand, is completely broken. It usually crashes within 5 minutes and it only supports up to 2msps. They haven’t updated it since Feb 2019.