The city of Shenzhen in southern China’s Guangdong province is home to global top handset providers Huawei, OPPO, and VIVO, and produces components and parts for Apple and Samsung, Xinhuanet.com reported on Nov. 27.

According to statistics by market research firm International Data Corp, Samsung, Apple, Huawei, OPPO, and VIVO topped the global sales volumes list of smartphones in 2016. Many producers and suppliers in Shenzhen have been manufacturing components and parts including chips, circuit boards, screens, and shells for their products.

Recently, a video of a foreigner assembling an iPhone 6s with components and parts purchased in Shenzhen for only 2,000 RMB ($303) went viral online.

“It’s not amazing at all, as Shenzhen owns the whole industry chain of mobile phones, which is unique in the world,” said Sun Wenping, president of the Shenzhen Mobile Communications Association.

For example, Shenzhen-based Chinese smartphone company Transsion Holdings is popular in Malawi for developing affordable products with cameras specially customized for African consumers.

Moreover, Shenzhen’s enterprises have been stepping up efforts to upgrade the homegrown chip industry.

Shenzhen-based Huawei made inroads with its Kirin chips and unveiled its first AI chip, Kirin 970, with superfast computing power and strong image-recognition capabilities. It powers Huawei’s new Mate 10 smartphone, which was launched to compete with Apple’s 10th-anniversary iPhone.

Apart from this, Shenzhen’s enterprises are trying to attract more talents to provide better services and products for people around the world.

For example, Huawei has set up research institutes in Russia and France to optimize its mobile phone design; Tencent has set up an AI lab in Seattle, US, to develop virtual assistant; and four institutes directed by Nobel laureates have been inaugurated in Shenzhen by April this year.