According to the latest market data findings from ABI Research (www.abiresearch.com), total system shipments for portable computing are predicted to reach 165 million units for full-year 2015, which is essentially flat compared to 2014 levels.

Assuming that the free upgrade promotion to Windows 10 OS offered by Microsoft is successful, much of the Windows installed base are likely to use their current computer hardware for at least a while longer. (The portable notebook PC category consists of four segments: netbooks, laptops, Chromebooks, and ultraportable PCs.)

"Segment growth is occurring in Chromebooks, much in part due to purchases by schools," says Research Director Jeff Orr. "Growth for 2015 is also in ultraportable PCs where thin and light designs are looking to tackle more mobile use cases by reversing the display panel flat like a tablet or having the screen separate entirely."

ABI Research says that Chromebook shipments are expected to increase 35% annually by the end of calendar year 2015 to seven million units. Sales led until now by North American educational buyers will yield to purchases in other geographic markets over the next 5 years, resulting in a 22% CAGR (compound annual return rate).

Ultraportable PCs, including the so-called 2-in-1 convertible and detachable display models, experienced typical season one seasonality with a 24% drop in quarter-over-quarter shipments to 7.2 million units, says the research gorup. Apple’s MacBook Air continues to lead all ultraportables. Laptops, the bulk of the notebook PC category, will experience a unit volume decline of about 7% year-over-year, says ABI Research.