Blue Barbel icon
Many times when I open Duolingo in my cellphone, on the homepage there is a blue circle with white barbel in it. This icon appears in all three languages I learn. but does not appear when I work/learn with a notebook When I touch these icon then immediately appears the exercise, not knowing what subject are they nor where they come from.
What does those icon means and what should I do with it?
Are you using an Android? This button doesn't appear on my screen and I use iOS. My guess is that it's a practice button, equivalent to the strengthen skills button on the web. It takes content from other lessons that you've learned and allows you to practice them. Once you complete it, you should receive 10 XP and it'll tell you which lesson you have strengthened.