With over 11 million units sold in its first month on the market, Samsung's (NASDAQOTH: SSNLF) Galaxy S5 is an unqualified hit.

And yet, no one should be surprised to read that. Despite stiff competition from Apple (NASDAQ:AAPL) and other Android handset makers, Samsung has emerged as the top dog, controlling more than 30% of the smartphone market in the first quarter.

Success has come with each new handset. From the Galaxy S selling 24 million units out the gate, to the S3 achieving 9 million pre-orders, to the S5's sparkling debut, Samsung is putting up the sorts of numbers you'd expect from a leader. A company capable of challenging Apple in its most important business.  

In the following slideshow, Motley Fool Senior Tech Specialist Tim Beyers provides a visual history of the Galaxy smartphone series and answers the question of whether now is the time to buy Samsung shares.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.