ByteDance’s Doubao AI phone – a limited-run handset built with ZTE’s Nubia brand – remained in hot demand and continued to receive frequent software updates, even as the device drew scrutiny over privacy and data security after its debut in early December. ZTE’s online store briefly reopened applications on Tuesday for an “F code” – a so-called “friend code” – that granted priority access to buy the 3,499-yuan (US$497) handset. Marketed as a “technology preview edition”, the device carried a...