While making an app it is really important to keep accurate track of the versions. Usually such a tracking is implemented via tags in version control system like git. It’s also a good idea to keep in mind semantic versioning when assigning version to your code.
But tagging your code with the right version number is only the first step. You also need to show version to the user and in some cases the system.
This –reblogged– post was actually drafted by the end of last year. I developed an open source Qt project then, namely Alldeb Installer and I wanted it to have the Git versioning to be used as part of the app’s version number.