PlayStation 4 and PSVita Releases: PCSX-R port for the PS4 has been released allowing you to emulate PS1 games and ElevenMPV 2.1.0 released with many fixes! - Wololo.net
Amazon.com: Pandaren Ps4 Console Full Skin Sticker Faceplates (PSone style Grey Skin X 1 + Controller Skin X 2) : Video Games
Even today I still play on ps1 here it is next to PS2 and PS4 : r/psx
Is The PS4 Backwards Compatible?
8Bitdo Bluetooth Adapter for PlayStation Classic Console/PS1 Mini (PS4 Gamepad) - Walmart.com
PS1, PS2, PS3, PS4, PS5 Size Comparison In Pictures - PlayStation Universe
EP 5) How to Run PS1, PS2 & PSP Games on a PS4 (9.00 or Lower!) - YouTube