A few months ago, Google made it possible for top Android developers to contact users directly and respond in the comments next to the Play Store entry for their apps.
This meant that users complaining about bugs could get help and that developers could offer their side in a dispute or simply say thanks to some comments.
This was available to the very top developers, with apps used by millions. Now though, it seems that Google has made it possible for all Android developers to get in touch with their users.
There are other ways to get feedback and help users, but this is probably the simplest and the most immediate.
Not only that, since it's public, other potential users can see how developers treat problems, leading to more installs and purchases.
It's particularly important for small developers who may not have the ability to offer support to their users via other means, certainly not via simpler methods.