The Samsung Galaxy S5 launched globally on April 11 and just a week later it grew to represent 0.7% of all active Android phones, says analyst firm Localytics. This compares to the 1.1% of all active iPhones that the iPhone 5s managed in its first week of sale.
http://cdn.gsmarena.com/vv/newsimg/1...marena_001.jpg

Still, it's important to note that Android encompasses a larger number of manufacturers and a far greater total number of phones than all iPhones. Localytics suggests that the busy Android landscape is partly responsible for the proportionally slower growth of the new Samsung flagship.
When the iPhone 5s came out, it was clearly the best iPhone, plain and simple. When the Galaxy S5 came out, there was the likes of the Sony Xperia Z2 and HTC One (M8) to contend with, making the choice for consumers harder (our Galaxy S5 vs. HTC One (M8) article is here to help).
The breakdown by regions is also quite interesting – despite South Korea being Samsung's home country and the Galaxy S5 launching there a few days earlier, it's the US that bought the greatest number of S5 units.
http://cdn.gsmarena.com/vv/newsimg/1...marena_002.jpg

Europe bought 23% of Galaxy S5 phones sold in the first week, compared to 28% for the Galaxy S4. Other regions accounted for 21% after the Galaxy S4 launch now comprise only 13% of total sales.
The US has so far been an iPhone stronghold, so Samsung will be pleased to see increased interest in its top of the line product.