Hello r/gamedev, I made this free little tool to test out controller inputs, since there's hardly a way to test them out without running a game or some other unrelated software :
Game Controller Test lets you try various game controllers on Android - Android Community
Joystick Test Application | Planet Pointy
Download Game Controller Tester 1.7.26.0
Game Controller Tester Gamepad on the App Store
Gamepad Vibration Test: How to Check Gamepad is Working or Not on PC | Videogamerplus
Gamepad Test | Controller & Joystick Test with Gamepad Viewer
Gamepad Testing for NES Gamepad and X-Arcade console adapters on PC. : Xgaming
ToS Gamepad Tester on Steam
Gamepad Tester - Aplicaciones en Google Play
ps4 gamepad tester – GamePad Tester
Joystick Test Application | Planet Pointy
Game Controller Tester by POW Games
GamePad Tester – Gamepad Tester
Gamepad Test | Controller & Joystick Test with Gamepad Viewer
How to test a game controller input on Windows 10
Game Controller Tester
Game Controller Tester - Download
How to TEST your Xbox One Controller - YouTube
How to fully test your ps4 controller including touchpad, vibration, motion sensor and speaker - YouTube
How to test a game controller input on Windows 10
HTML5 Gamepad Tester - Test your gamepad online! — Steemit