TubeBuddy is a chrome web browser (PC and MAC) extension (also can be added to Firefox web browser with little modification) which allows you to edit the videos that you upload to youtube.
After you add the extension click the extension and sign in to your youtube account and give the required permissions. Once you do that you will see Tubebuddy signature on the extension.
Tubebuddy suggest you Video SEO ideas to make your videos and channel popular. More subscribers, more watch and more view time. Which will lead to more income.
In addition to SEO, tubebuddy comes with many audio library which will make your videos cool!
Tubebuddy is FREE, for additional features you can pay fees as low as $3 per month. It has discount for low subscriber count channels and another discount for yearly payment.