Various Gameplay Tips
In this game, there is no need (or ability to) click - the only way to earn is to sit there and watch the money pile up as your tubers earn views. The more of them that you combine together, the more overall views and money you'll earn. You can also spend money to purchase more characters for your merging space instantly, without having to wait.
The best use of money in the game, though, arguably, is to go to the upgrades area and purchase the permanent boosts. The auto-watch bots will earn you more money while you're offline and the auto-fuse magnet will allow you to set the game down and let it do the fusing for you - which is useful because the manual fusing on this game can be very difficult to line up sometimes.
Once you unlock a new youtuber, head to the store and check for any new unlocked available characters. If a character costs less than twice as much has the character directly above it, then it's a good deal. If it costs more than twice as much as the directly previous character in the shop, then it's still overpriced for the time being and is not a good deal.
Gems are kind-of, sort-of the premium currency of the game, but not really. For one, they pop up constantly as a reward for merging tubers together. For another thing, they only buy one thing in the entire game, and that is new outfits for your characters. The outfits are cool for modifying their appearances, but they have no practical effect besides that.
If you want to earn money a lot quicker, hit the 2x button in the upper right corner of the screen. When you do, an advertisement video or mini game will appear, and then when the video or mini game is done, you will have a 2x boost for an hour. Keep hitting the 2x button to keep adding boosts onto the end of your last boost, to increase it from 1 hour to two hours, three hours, etc. as the videos go on.