Xcode could not locate the installed application

Run you code in debug mode instead release mode. you can change to debug mode from edit scheme.

This popped up for me. I was able too solve the problem by selecting "Automatically manage signing" on the Signing and Capabilities tab of the Project's application target configuration panels.

Interestingly, I was able to then change it back and it installed, ran and debugged properly. Go figure

The only solution I've found is by simply changing the bundle identifier. But I could not find what is wrong with the previous identifier while I used it in xcode 10 as well and it was working fine.