With apps being constantly developed, competent app developers are in high demand. Again, if you have the experience or skills to create successful apps then this could be something you could end up working on as a full-time freelancer. Check out adverts for developers on Toptal, a higher paying jobs site for experienced freelancers wanting to make money online.
It may take time to build that audience that turns views into dollars. The average revenue per 1,000 YouTube views is just over $6. But with enough videos for fans to scroll through, those views can add up over time. While you're building an audience, you could also join an affiliate program related to your channel and make money through affiliate links in your video descriptions.