While in recent years, Apple Inc.’s (AAPL) iPhone has driven the boom or bust cycle among parts suppliers in Asia, investors are now shifting their attention to a new type of product that is now on track to become the "next big thing” in the consumer electronics space.

As e-commerce revolutionizes retail, smart speakers—which are voice-activated internet-connected virtual-assistant devices such as Amazon.com Inc.’s (AMZN) Echo—are gaining popularity among consumers as they use them to make orders. Other global tech giants including Alphabet Inc.’s Google (GOOG), Samsung Electronics Inc. and Chinese competitors such as Alibaba Group (BABA) have jumped on the trend following Echo’s 2014 debut, spiking demand for components including semiconductors, speaker modules and motion sensors.

The supply squeeze has worked in the favor of a large number of Asian suppliers including China's Hua Hong Semiconductor Ltd., and, Taiwan's Primax Electronics Ltd. and WIN Semiconductor Corp. WIN is among the Asian tech stocks held in two exchange-traded funds, SPDR S&P Emerging Small Cap ETF (EWX) and iShares MSCI Emerging Markets Small-Cap ETF (EEMS). (See also: Amazon Releases Echo Show (Alexa With a Screen).)

A 'Smartphone Moment'

Old Mutual Global Investors, an investment firm with over $37 billion in assets under management, indicates that smart speakers are just taking off, reports The Wall Street Journal. “We’re in the early stage for this rollout, and we don’t think it’s fully priced into the stocks,” said investment director Oliver Lee. He foresees smart speakers reaching a “smartphone moment,” expecting the devices to become the norm over the next three to four years.

Sales of smart speakers are mushrooming. Gartner forecasts spending on the devices to total $3.5 billion by 2021, up from $360 million in 2015. According to research from Consumer Intelligence Research Partners, 10.7 million Americans owned an Amazon Echo at the end of Q1, compared to just 3 million one year ago. (See also: Apple iPhone 8: Leak ‘Confirms’ a Price of $999.)

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