you-tldr - Get the tldr of any YouTube video in seconds
hashtags.org - Hashtag is an extensive hashtag research platform for analytics and tracking of hashtags, providing...
tubecut. - The only YouTube downloader allows you to trim specific time
HSHTG - Generate, manage, save and edit hashtags just in a few finger tap
Matstad - A Reddit style YouTube app
RiteBoost - Auto-hashtags, Auto-emojis, GIFs and much, much more, all according to your Enahce rules.