I am in love with Canva! It's full of templates that fit all kinds of marketing needs. Flyers, post cards, memes, etc. It's rather addictive so be warned. You have a ton of templates which look amazing on their own but you can truly customize anything to heart's desire. If anything, you can get inspiration.
The really cool aspect is being able to choose sizes for a multitude of platforms too. Facebook covers, Instagram posts, business cards, etc. The possibilities are truly endless.
It took me a bit to really uncover all of its glory but there's no shortage of fonts, icons, colors and even free images to use in making your next great marketing piece. I particularly love the real estate flyers for listings. So modern and beautiful.
They do have an app as well which is very convenient but I prefer using on my laptop for better visual control. Just a personal preference. I used Canva to make a buyers and sellers guide and I cannot be more thrilled with the results.