What or where are challenges?

Question

I see there are a number of badges for challenges, but I don't see any link to such an area to find challenges. Do I have to finish a course first before I can see challenges? Do I have to be invited to a challenge? Enlighten me, please.

Answer 1

if you are using web version of sololearn, you won't find it
else if you are using android version, it's the second tab from left that looks like thunder

Answer 2

go to your main menu,youll see five different sections.
lessons
challenge
home
codes
posts.....
click challenges,look at your right bottom corner youll see a green "+" sign.click it and a list of people will pop up.click on anybody and youll understand whats with the rest

Answer 3

click on second icon in tab when you open sololearner it's lightning like icon then in that tab click on plus icon to start new challenge choose your weapon, weapon in the sense programming language. Then choose an random opponent or someone your already following or your follower of, there will be 5 questions and winner will be decided according to correct answered questions.

Answer 4

I am using the web version. So I can't do challenges?