The latest figures by ComScore indicate Apple is rapidly catching up to its staunch rival Samsung, which remains at the top of the US smartphone market-share rankings, Cnet has reported. On platform market share, only Apple and Google managed to secure an increase in subscribers, while the other platform makers saw a decline. Apple's smartphone share grew 2.1% in August, the highest increase in mobile subscribers seen since April, edging closer to second-place smartphone maker LG, which dropped by nearly 1% in the three-month average period ending in August. BlackBerry maker Research In Motion saw the greatest loss with 3.1% in the platform space. Microsoft's Windows Phone and Nokia's Symbian operating systems declined by 0.4% each, the data showed.