{"id":204,"slug":"mobile-nav-sequential-not-split-button","title":"NN/g: split buttons unreliable on touch (fat-finger conflicts) — use sequential menus or accordions on mobile","kind":"reference","scope":"business","status":"current","audiences":["claude-code","dev","candid-team"],"topics":["navigation-design"],"reference_body":"**Claim:** Per NN/g's mobile-navigation research, split buttons for navigation (where part of the button navigates and part expands a sub-menu) are **unreliable on touchscreens** due to fat-finger conflicts — users frequently hit the wrong half. The safer mobile patterns are **sequential menus** (each level replaces the previous) and **accordions** (expand-in-place).\n\n**Source:** NN/g mobile navigation research (foundational guidance, current 2023-2026).\n\n**Confidence:** Industry-consensus.\n\n**Caveat from the brief's honest-gaps section:** Mobile navigation patterns for **multi-vertical service businesses specifically** are underexplored in current research. NN/g's mobile mobile-subnavigation guidance applies, but no recent (2024-2026) study tests multi-vertical service-business mobile nav directly. Use the NN/g principles; don't pretend there's field data specific to this case.\n\n**The safe pattern: desktop mega menu + mobile accordion**, not a single nav pattern across breakpoints. See [[nng-megamenu-dont-cover-entire-screen]] for the desktop side.","rationale_body":null,"metadata":null,"links":{"outgoing":[{"slug":"nng-megamenu-dont-cover-entire-screen","title":"NN/g: \"On large screens, don't cover the entire screen when megamenus are open\" (Apr 30 2023)","kind":"reference","scope":"business","link_type":"relates-to"}],"incoming":[{"slug":"rule-implement-megamenu-with-hover-delay","title":"RULE: Mega menu hover delay 500ms before show, 100ms reveal. Mobile uses accordion / sequential, not the same mega menu.","kind":"rule","scope":"business","link_type":"depends-on"},{"slug":"research-brief-ia-multi-vertical-service-business","title":"Research brief: Information architecture for service businesses with multiple verticals (piece 6 of 15)","kind":"reference","scope":"business","link_type":"relates-to"}]},"created_at":"2026-05-22T19:40:49.123Z","updated_at":"2026-05-22T19:40:49.123Z"}