On what apps to use with a RSP, I prefer HDSDR if only a single channel is so be monitored, with SDRuno following closely. Nothing beats HDSDR for simplicity as well as for low cpu usage, but I find SDRuno to have the best agc and audio at the cost of high cpu usage and utter complexity.
For multiple VRX work, SDR Console is my goto as it is very foolproof, very stable, great aduio and agc action, and much reduced cpu usage compared to the same number of VRX in SDRuno. SDRuno sure looks great tho.
On recording, any app should be able to make good audio frequency recordings. Considering a max bandwidth of say 3kHz for a single ssb channel, you only need an 8kHz recording rate, making for tiny files so you can pack more on a disk. For voice recording, audio freq is best, for digital modes, IQ recording would be better but take up a bit more disk space.
Some guys go hog wild like the NSA and record entire swaths of spectrum as IQ, saving it to disks, a few gb or more for a few hours recording is typical for a hobbyist. I imagine the NSA and its counterparts worldwide go through a few hard drives. I prefer to have the audio recording always on, and have it on a loop so it overwrites as time goes on, this way I have a copy of what ever of interest pops up without running out of disk space. A dedicated drive is a plus, and I still prefer ludite spinning metal to the bleeding edge solid state (aka flash) drives for reliability.