[endless1234]

In general, they were not. You're probably thinking of the very niche and unsuccessful Maemo/MeeGo project - eg Nokia N900 - that were indeed Linux-based. But everything else smartphone-ish from Nokia before Lumia (Windows Phone) were Symbian, which predates Linux and has nothing to do with it.

[nextos]

I am of course referring to Maemo, as per my previous post.