Galaxy S6 sales reportedly hit "over 10M" at an unknown date.
http://www.gsmarena.com/samsung_galaxy_s6_shipments_surpass_10m_behind_schedule-news-12322.php
The Galaxy S5 hit 10M
shipments at 25 days after launch.
Note how I bolded "sales" and "shipments". Samsung shipped 20M Galaxy S6 units before the Galaxy S6 even launched. Whereas the Galaxy S5 took 25 days to ship just 10M units.
So if we interpret this correctly, the Galaxy S6
sold as many units in the 1st month of release as the Galaxy S5 got
shipped in its 1st month of release.
That's a HUGE difference, meaning that the Galaxy S6 sold 10M in the 1st month release, whereas the Galaxy S5 may have only sold ~5M in the 1st month of release.
Also since the Galaxy S4 ended up selling much more than the Galaxy S5, it's too early to tell whether the Galaxy S6 will end up selling more than the Galaxy S4/S5.
With production issues for the Galaxy S6 Edge, and with the Galaxy S6 Edge variant making up 50% of total Galaxy S6 sales, this might be hurting Samsung in the short term. However, in the medium term, Samsung will be able to manufacture substantial Galaxy S6 Edge numbers, meaning it will sell much more in the end of Q2/Q3.
So we may see a larger growth in Galaxy S6 sales by September.
Also I don't think Samsung is fully focused on smartphone sales anymore. The soon-to-be CEO, Lee Jae-young, is actually focused on electric vehicles and autonomous driving technology now according to numerous sources.
Since Samsung overtook Apple in worldwide smartphone market share in Q1 2015, expect this to become even more pronounced by Q3 2015.
Apple is going to rely heavily on their next iPhone, the iPhone 6S. If the iPhone 6S sells well, then expect Apple's market value to reach $1 trillion USD. If it doesn't sell better than the iPhone 6, expect Apple's market value to plummet.