Ars calculates the size of the DualShock 4 touchpad: about 2.1” x 1”

A little image wrangling (and math) generates a general sizing estimate.

Precision Control: The feel, shape, and sensitivity of the DualShock 4 s analog sticks and trigger buttons have been enhanced to offer players

DualShock 4 - White

The PlayStation 4's touchpad and the law of unintended consequences - The Verge

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Controller Touchpad Board for Sony Playstation 4 Dualshock 4 Replacement Part

Use Touchpad of DS4 controller as a button (PC) : r/RocketLeague

Game Controller Repairing Touch Pad Accessory, Wearable and Durable Replacement Touchpad for PS4 Gamepad : Video Games

PlayStation Controller Dimensions & Drawings

Powkiddy X28 Handheld Game Player Android 11 T618 5.5 Inch Touch IPS Screen Handheld Retro Game Console Gift Free Shipping - AliExpress

PlayStation Controller Dimensions & Drawings

ISO 9241-9 Evaluation of Video Game Controllers - Department of

The PlayStation 4's touchpad and the law of unintended consequences - The Verge

Smart controller: Introducing a dynamic interface adapted to the gameplay - ScienceDirect

Project Caliper: the journey of prototyping optimal controllers for VR - The Ghost Howls

GCDualShockGamepad Apple Developer Documentation

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