Chinese consumer electronics manufacturer, a subsidiary of Oppo
OnePlus Technology (Shenzhen) Co., Ltd. (Chinese: 一加科技; pinyin: Yījiā Kējì), doing business as OnePlus, is a Chinese consumer electronics manufacturer headquartered in Shenzhen, Guangdong, China. It is a subsidiary of Oppo. OnePlus was founded by Pete Lau and Carl Pei on 16 December 2013 to develop a high-end flagship smartphone running Cyanogen OS that would come to be known as the OnePlus One. OnePlus would continue to release smartphones afterwards. In 2020, OnePlus released the OnePlus Nord, its first mid-range smartphone since the OnePlus X in 2015.
https://en.wikipedia.org/wiki/OnePlus