A study comparing a traditional reaction-time platform with an iPad and iPod Touch found similar simple-reaction results across the three platforms: roughly 300, 287 and 280 ms respectively. Choice reaction time differed more, with the traditional platform faster than the mobile devices in that experiment.
Those numbers should not be treated as a permanent ranking of “mouse vs touch.” They came from specific hardware and software. Modern devices vary widely in touch sampling, display refresh, browser behaviour and input latency.
For a full-screen simple reaction test, the finger may already be resting on the screen while a mouse user may already have a finger on the button. The movement component is tiny.
For an aim test, the task changes: you have to acquire a target. Touch lets you point directly at the visible location, while a mouse maps hand movement to cursor movement. Target size, distance and accuracy then become major factors.
Human-computer interaction research models these pointing tasks using Fitts' law: movement time changes with target distance and size. Touch also has the well-known “fat finger” ambiguity, especially for small targets.
Research on online and mobile reaction testing has warned that consumer hardware can introduce significant timing differences. Touch sensing, display processing, operating-system scheduling and software all contribute to the measured number.
That is why Reaction Lab does not merge mouse and touchscreen results into a universal leaderboard. If you want to track improvement, stay on the same device and input method.
For the cleanest comparison, run Classic on both devices, then try Aim on both. You may find that your simple reaction score and your target-acquisition score favour different inputs.
Continue with: Mobile vs desktop reaction time · Input lag vs reaction time · Fitts’ law and aim speed · Improve click accuracy.