Easily one of the most successful consumer products in history. Nearly half a billion iPads have been sold since 2010, with around $300 billion in sales in those ten years.
In electronics & tech, the good scale comparisons are few, things like the iPhone, Mac, Windows, Nintendo, PlayStation, Xbox.
To put that $300b into better context, that's equivalent to the total sales of Windows throughout its entire 30 year history up to about 2014. The iPad will probably end up being the second best selling consumer technology product of all-time behind the iPhone. It has already well passed the iPod in units and dollar sales.