"Anyways" is North American slang. Sometimes they say also, "Anyhoo", which is slang for anyhow. But they can only say "Anyhoo" if the "Anyhow" means "Anyway". If "Anyhow" means n'importe comment, then you have to stick with anyhow. But if anyhow means en tous cas which means anyway, then they can use anyhoo. Usually you use anyhoo au seuil pour vouloir dire que vous voulez finir la conversation et partir. Et puis on dit fermement et au ralenti "Any-hooooooo!", juste comme au seuil (ou au téléphone pour finir l'appel) on dit "Any-waaaayz". C'est clair? Ha, ha, ha. Dave

It depends on how it's used. If it's used like "Anyway, it doesn't matter." you can use either. If it's used like, "I can't do it anyway." you would be more likely to not use "anyways."

http://grammarist.com/usage/anyways/