The analyst firm Strategy Analytics believes that Google's Android mobile OS is nearing the "peak" of its popularity.
New data for the US market in the second quarter of 2012 - reported by TechCrunch - shows Android slipping in both millions of units shipped and overall market-share.
Android phones shipped 13.4 million units in the US in the second-quarter, significantly down from the 15.3 million shipped in the same quarter last year. As a result, Android's market-share fell from 60.6 per cent to 56.3 per cent.
Google's OS, which is supported by a wide range of mobile devices, still has the controlling share of the US market, but while its hold appears to be slipping Apple's iOS is on the rise: shipments of iOS devices increased from 5.9 million to 7.9 million, and its market-share grew from 23.2 per cent to 33.2 per cent.
The problem for Google is that, while companies like Samsung are producing very popular Android devices, Apple is apparently poised to launch a new iPhone in the near future. The resulting increase in demand for iOS devices could prove decisive.
"Android's...market share is approaching a peak and Apple iOS has been gaining ground," said Strategy Analytics' executive director Neil Mawston said in a statement. "Apple is rumoured to be launching a new iPhone in the coming weeks, and that event, if it takes place, is going to heap even more pressure on Android in its home market."