I like ProScan it has numerous features and great support. A quick search will show others. Freescan (no longer supported) and ARC (XT) I believe for this model.
Should you need to deal with DMR or NXDN, you would need to use either ProScan, or ATC-XT. Like freqseeker has suggested, ProScan is a much better choice, and also supports a number of other Uniden scanner models.
I like ProScan it has numerous features and great support. A quick search will show others. Freescan (no longer supported) and ARC (XT) I believe for this model.
Butel ARC-XT PRO is what I use. It comes two ways, BASIC or PRO. Uniden doesn’t make a software program for the 325P2 as there are third party offerings free of charge or paid. PROSCAN seems to be the more popular as it also supports other Uniden scanners, as stated by others here.