The O2 Xda brand was a range of Windows Mobile PDA phones, marketed by O2, developed by O2 Asia and manufactured by multiple OEMs (mainly HTC, Quanta and Arima). The first model was released in June 2002. The last models came to market in 2008. The "X" represents convergence of voice and information/data within one product; the "DA" stands for "Digital Assistant", as in PDA. The name of XDA Developers is derived from it.