Accesibility

Fitts’ Law proves that target size and distance dictate interaction speed and precision. Designing interfaces around this principle directly improves physical accessibility for users with motor impairments, tremors, or single-handed mobile usage.

Core recommendations

Enlarge the Interactive Hit Area: expand target dimensions without inflating the visual icon itself. Use generous CSS padding around icons to meet minimum WCAG accessibility standards (44×44 CSS pixels for WCAG 2.2 Level AA; 48×48 dp on Android).
Minimize Cursor & Thumb Travel: place dependent actions adjacent to the trigger point. Contextual menus, inline actions, and popovers reduce pointer travel compared to fixed top-corner control panels.
Leverage Screen Boundaries: on desktop UIs, screen edges and corners act as "infinite targets" because the pointer cannot overshoot the display boundary (e.g., system taskbars or top menu bars).
Maintain Target Spacing: Provide at least 8px of clear spacing between adjacent interactive elements to prevent accidental mis-clicks or taps from adjacent actions.

Interface Pattern	Application of Fitts' Law	Accessibility Benefit
Mobile Thumb Zones	Placing primary CTAs, search bars, and main navigation in the bottom third of mobile screens.	Reduces thumb stretch and allows comfortable single-handed operation without regripping.
Sticky Action Bars	Pinning "Submit", "Save", or "Checkout" buttons to the viewport during long form scrolling.	Keeps distance ( $D$ ) near zero regardless of how far a user scrolls down a page.
Radial / Context Menus	Displaying options in a ring surrounding the cursor upon right-click.	Equalizes and minimizes distance ( $D$ ) to all choice items simultaneously.
Full-Width Mobile Buttons	Extending primary action buttons across the full width of mobile viewports.	Maximizes target width ( $W$ ), drastically speeding up tap accuracy.
Destructive Action Isolation	Moving "Delete" or "Reset" options further away from routine primary actions.	Intentional friction via increased distance prevents high-risk accidental triggers.