The newest versions of Apple's (NASDAQ:AAPL) iconic iPhone line --the iPhone 6 and 6 Plus -- continue to reward the company's investors. After selling nearly 75 million iPhones in the new models' first full quarter of availability, 46% more than in the same period a year before, Apple sold 61 million smartphones (a 40% year-over-year spike) in the recently reported second fiscal quarter as China registered strong sales growth.

These results, though, are nothing without context, and third-party research estimates help to ascertain Apple's performance versus its peers in the smartphone market.

If a new report from research firm Gartner is accurate, Apple is outperforming its peers in the heavily contested smartphone market.

Winning worldwide market share
In its market share survey of worldwide smartphone sales to end users for the first quarter of 2015, Gartner showed Apple delivering 60.2 million units in iPhone sales. That is in line with Apple's previously reported figure of 61 million, and points to the tech giant increasing its market share from the previous year. Per Gartner's survey:

Company Q1 '15 Units Q1 '15 Market Share Q1 '14 Units Q1 '14 Market Share
Samsung 81,123 24.2% 85,507 30.4%
Apple 60,177 17.9% 43,062 15.3%
Lenovo 18,888 5.6% 16,721 5.9%
Huawei 18,102 5.4% 13,450 4.8%
LG 15,428 4.6% 11,200 4%
Others 142,335.6 42.4% 111697.8 39.7%
Total 336,054.4 100% 281,636.8 100%

Units figure in thousands. Source: Gartner. Bolded lines signal market share growth.

Apple's 40% year-over-year sales growth in the first three months of the year is even more amazing in that it doubles the overall market's unit growth of 19.3% shown in Gartner's numbers. In the process, Apple increased its market share by 2.6 percentage points, the most among named companies (the catchall "others" category actually grew by 2.7 percentage points). That narrowed Samsung's market share lead from 15.1 percentage points in Q1 2014 to less than half that at 6.3 percentage points for this year's first quarter.

Samsung's shrinking market share
For Samsung (NASDAQOTH:SSNLF), this is continued bad news on mobile unit sales, but also nothing new. The Samsung's Galaxy S5's underperformance has been widely covered. In the second quarter (after the period covered by the Gartner survey), Samsung released its Galaxy S6 to much fanfare, but conflicting corporate communication regarding sales estimates has tempered expectations somewhat. Regardless, Samsung was the only named vendor in Gartner's report to experience a year-over-year decrease in unit shipments as Apple stole market share at the high end and other vendors attacked it at the low end.

Other vendors to watch
Huawei and LG each posted first-quarter units sold figures that outstripped the market's overall rate of growth. While these vendors are relatively small compared to Apple and Samsung, they have the ability to disrupt market share figures going forward.

Recently, the rumor mill has heated up about Google's (NASDAQ:GOOG) (NASDAQ:GOOGL) next Nexus phones. According to the Android Police website, Google plans to introduce two variants, with the smaller unit manufactured by LG and the larger, phablet-sized version produced by Huawei. While Google's Nexus line hasn't been the game changer many envisioned, the devices should help both companies ship more units thanks to its small but fervent user base.

Recently, Google unveiled its Project Fi MVNO carrier service, which is only available for those with Nexus phones, as the search giant seeks to become a total provider of the mobile experience, from smartphone design to operating system to actual network delivery. It's an ambitious plan, but could give a shot in the arm to any Nexus manufacturer if its plan finds a receptive audience. If so, this could put further pressure on Android-based manufacturers such as Samsung going forward.

In the end, while this is historical data and investing is about looking forward, you have to like Apple's future, be worried about market leader Samsung, and watch LG and Huawei for possible disruption.