Trying the new Youtube beta studio sums up @YouTube @TeamYouTube in a nutshell.pic.twitter.com/15t2Rc8edf
You can add location information to your Tweets, such as your city or precise location, from the web and via third-party applications. You always have the option to delete your Tweet location history. Learn more
It's not an "app", it's the normal web browser interface.
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