I think (a good) changelog is especially important when it comes to closed-source software where you don’t have the opportunity to downgrade easily (from Windows software to mobile applications).

For example if you visit the App Store now, you’ll see the many app developers, especially the big ones such as Twitter, Facebook etc., are using the same changelog entry for every, single, update: “Thanks for using X! To make our app better for you, we bring updates to the App Store regularly.” The problem is, this doesn’t tell me anything about what to expect. No, I see that I shouldn’t have anything to worry about because the new features are throughly UX-tested, and as an app end user there is not much to consider anyway (it’s not a framework I’m using in production, right?).

The problem is, the changelog matters when Facebook removes messaging functionality to push its users to their new app for some for-profit reason. Changelog matters when your favourite app which has been free for the past couple years have decided that it’s monetisable now and there are intermittent ads in your feed. It matters when they think you don’t need a functionality anymore and proceed to remove it, but you actually do.

I think changelog should be enforced far, far more strictly for closed-source software, and especially for those on App Store and Play Store.