The official app includes a lot more than just the basic features you need. 

The Polyglot VK app offers users the ability to go unnoticed on VK. This prevents them from being seen by others on the site, and it doesn't work when viewing messages and news. As you use this app, it will appear that the other party is unaware that you have been reading their communications thanks to this software.

Additionally, you can create up to four separate user accounts on your account, which can be easily switched between.

Lastly, you can protect your messages so that no one can access them, and you can also unhide friends to see who they are hiding from you.