China’s Honor Launches World’s Thinnest Foldable Phone

Chinese smartphone brand Honor launched what it claims is the world’s thinnest foldable phone—just 4.1 millimeters thick when unfolded, as it seeks to regain lost ground in China’s competitive phone market, Nicholas Gordon reported for Fortune Tech.

As of the first quarter of 2025, Honor held a 13% share of China’s smartphone market. I Photo: Honor Singapore Facebook

The Magic V5’s slim profile is made possible by innovations in its silicon-carbon battery, which stacks cells just 0.2 millimeters thick to create a power source as thin as a bank card.

The phone is also lightweight: at just 217 grams, the Magic V5 weighs less than the iPhone 16 Pro Max. Honor says it invested 1 billion Chinese yuan ($139 million) in researching its silicon-carbon battery technology.

The company allocates over 10% of its total revenue to R&D each year. “In terms of materials, structure, craftsmanship… everything is extremely costly from an R&D perspective,” Hope Cao, Honor’s product expert on foldables, told Fortune.

Foldables represent a small but rapidly growing segment of the Chinese smartphone market.

Sales in the category grew 27% last year, according to Counterpoint Research. Book-type foldables—which open along the longer edge to create a larger screen—are particularly popular.

Honor was formerly the budget smartphone division of Huawei, but U.S. sanctions forced the Chinese tech giant to divest the brand in late 2020. As of the first quarter of 2025, Honor held a 13% share of China’s smartphone market, according to Counterpoint, close behind Vivo, Oppo, and Apple.