Voices of Search has a great podcast out about mobile SEO. Check it out on your commute to work!
As you probably know, Google is switching to mobile-first indexing which is going to have a huge impact on SEO as a whole. Your mobile site really needs to be performing well!
On optimizing for mobile they said, "It is that swipe, that quick click, that ability to shift into other content within your experience very quickly, is ultimately what the optimization of those menus will do for the user, but those user signals, along with the ability for Google to navigate, and crawl that is the secondary benefit that you generate from that."
Give it a listen and let us know what you think. What have you done to optimize for mobile?