This blog post teaches you to make simple iPhone app in Swift Programming Language and in what way to use Objective C file with the Swift Project. You can make the Objective C file and also import from any folder of your Swift Project.
How to turn ON/OFF camera flashlight in iOS, this is our main objective. There are so many users; those are using turn on flashlight with one button and turn off flashlight with another. But here I want to do it with a single button only.