I've carried some handguns that aren't exactly 'pocket' pistols.
But the two smallest handguns I own are a Beretta Tomcat, 32 ACP
and a snubnose, S&W 432 PD, 32 H&R Mag.
Both handguns fit comfortably and securely in many jacket pockets and Dockers hip pockets that I wear.
As far as a holster goes, something like Uncle Mike's $9.00 Inside-the-Pocket Holster keeps the handgun in place,
clean, and accessable.
Nothing hi-tech or tactical - but it suits me.
I had a 3 inch 360PD with a CT lazergrip for a long while, and it was a terrific all around compact handgun. Wish I had it back.