As I need to create multiple virtual switch manually for my DIY universal IR project & link them to SmartThings & Echo.
I decided to follow the earlier examples below & come out with a version of HTTP Switch Creator.
tguerena and surge919 - URI Switch
Eric Roberts (baldeagle072) - Virtual switch creator
JZ - TVDevice
You need to install both device handler & smart app. Once install, you can create virtual http switch/button on the fly
HTTP Button handler (v1.1 - corrected the button behavior and more like momentary switch):
HTTP Button Creator: