Yes, but if you can load a few lessons (assuming you're using the mobile version), but only a few...
Duolingo was created in 2011.
yes,
Many products on the market today require wifi to work. Many of the smartphones today require an internet connection of some sort, usually wifi, to be able to download apps or do anything really on the phone.
Duolingo and Memrise. I recommend duolingo.
Duolingo is 100% free. They want free language education for everybody.
From what i hear, draw something does not require wifi.
no
you can download the Duolingo mobile apps and can learn there free of cost.
Data is wifi. The only way a smartphone can use wifi without having a data plan is when it is connected to wifi at a building.
Yes, according to Duolingo's guidelines, it is recommended to wash your feet.
No, unless the place you are at require a charge to use their Wifi, but normally it is a free service
Yes, it will require an internet connection. Just like Skype ;)