AmbiBench: Benchmarking Mobile GUI Agents Beyond One-Shot Instructions in the Wild. - Jiazheng Sun; Mingxuan Li; Yingying Zhang; Jiayang Niu; Yachen Wu; Ruihan Jin; Shuyu Lei; Pengrongrui Tan; Zongyu Zhang; Ruoyi Wang; Jiachen Yang; Boyu Yang; et al. (CoRR, 2026)