Any time you stick in a memory card the app launches, and I NEVER use that app. I need to use Bridge and Photoshop, and I hate that stupid Photo app always running.
There are solutions, but normally you have to set them on a card-by-card basis. Which is not acceptable. I found a better way, thanks to Thorin Klosowski at LifeHacker. He published this tip in January 2016. Open a Terminal window, and type (well, copy/paste) the following command:
defaults -currentHost write com.apple.ImageCapture disableHotPlug -bool true
That’s it. Run this command, and the program will never launch again. Well, it won’t until the next major OS update, which I guess will be the end of OS-X and the first release of Mac OS.