Various application scenarios of a smartphone sometimes require one-handed and/or eyes-free interaction. Tilt-based interfaces have the potential to meet these requirements. Taking multiple application scenarios into account, we conducted an experiment to systematically investigate human ability in controlling tilt input of a mobile phone. Three visual feedback levels, i.e., fully visual feedback (FV), partially visual feedback (PV), and no visual feedback (NV), were investigated. Under the NV condition, the participants performed a task using an eyes-free method. The results revealed that trials were performed the fastest but were the most error-prone under the NV condition. The participants could easily distinguish 4 tilt orientation levels (TOLs) and 2 tilt magnitude levels (TMLs) or 8 TOLs and 2 TMLs under the NV condition with tolerance of an error rate 10% or 15%, respectively. We also found out that the participants’ abilities to control tilt input were related to tilt orientation directions. The results have some implications for non-visual interface designs using tilt as primitive input.