User education
A compelling product principle I learned from the founders of WhatsApp was to never show a popover to point at something in the UI. Their thinking was if you needed to do this, the UI was not obvious enough in the first place.
Education UI generally tends to be interruptive to the user and not be very effective in its goal. In many cases it ends up annoying the user by disrupting their flow or pointing them to features they do not need.
Designing without the crutch of education UI truly forces you to make the core UX as simple and obvious as possible. If someone looks at an interface and has no questions about how to use it, you have succeeded at good UX.
Apple has a similar principle when it comes to education. While they do have a framework specifically for showing tips, the intention is to show the tip to least amount of users under the most specific conditions.
The tips often target active and mature users who are not using the most efficient version of the UI. The goal is to save them time in their pre-existing actions, more so than to promote features.
It is helpful to consider who you are targeting with your education. Early adopters rarely need this kind of education because they are natural explorers. Later adopters might be getting all the value they need out of your app. It is good to question whose needs you are serving by trying to direct the user's attention.
Another education technique often overlooked is social sharing. It is a powerful and natural way for users to learn deeper UI paradigms, i.e. 'oh did you know you can do xyz?!' People will share interactions they find valuable and the information will be more trustworthy as a friend's opinion makes a stronger impression than a generic UI element.
At WhatsApp I worked on a feature called 'swipe to reply'. This is a non-obvious interaction that allows you to swipe a message to reply to it. People found this feature faster than long-pressing a message and tapping reply. They naturally socialized how to perform the behavior in group chats and online posts.
Because people were finding significant value out of the feature, we added a one-time self-dismissing toast for users who replied to a message using the traditional method but had never discovered 'swipe to reply'. The idea was to give them feature awareness without interruption. It did add additional awareness to the feature and ended up being a big success.
Not every user will immediately understand every feature in your app, but making the most obvious and simple UX possible should be your primary goal. I also encourage you to be patient with your users. Let them discover and organically educate each other about advanced features. If you do decide to educate your users, try to do so in a highly targeted and non-blocking way.