The average Cambodian guy doesn't have a smart phone, you will find them using some old Nokia from 15 years ago... so don't expect to find them on any gay apps
Of course some do have smart phones, but they will either be ex MoneyBoys after arriving back home from Thailand, Current MBs, "kept" boys or guys from rich families...
As for the partying, I like PP and can tolerate SR, but have a loathing for the FWCs (Fat White Cows, haven't seen that phrase used in a while!) that tend to hang around the gay bars, scrounging drinks, or not even drinking at all, whilst looking down their noses on GWMs and their Cambodian company.
Similarly I have a loathing for dreadlocked backpackers and people wearing fishermans pants!
I think you will be disappointed to learn that Cambodia is definitely not the gay Mecca that you seem to think it is!
Spend 3 days each in SR and PP and spend the rest in Thailand if you are looking to get laid and party!