It's an Android app called "Stellar Browser" which is actually useful for downloading videos from many sites, and the author recently added Naver "V" to its arsenal. Here's how it works:
Using Stellar Browser
Open the app, and click the "V" to go directly to the V live homepage, or you can just visit the page manually.
You obviously cannot download live videos, but once the broadcast is finished, you can download.
Go ahead and find that dreamy new EXO video.
Press the green "high quality" version button. The orange download arrow will appear at the bottom of the Stellar browser. Press it!
Swipe right in the browser to see the list of your downloaded videos.
Downloading Stellar Browser
Because this browser can download videos from various sites (most importantly, from YouTube), Google does not allow it in the Play Store.
However, it is available in various other app stores:
- Stellar Browser 1.232을 위한 Android - 다운로드
- Stellar Browser 1.232 for Android - Download
- 스텔라 브라우저 - V앱, 유튜브 다운로드 | ONE store
- Stellar Browser - V Live, YouTube Downloader free app download for Android
Special credit to 세바스찬 from whose blog post I've taken and translated the information:
Future belongs to those who prepare for it today : 네이버 블로그