Airbags, visibility, controls, pedals and seat belts define no-go areas long before styling or convenience enters the conversation.
Map the non-negotiables
Never obstruct airbags, controls, visibility, pedals, seat belts, or structural parts. If the accessory cannot live outside those systems, the concept does not proceed.
Test the real conditions
A stationary fit check is necessary but incomplete. Materials and interfaces need heat and vibration validation, and removable modules should stay quiet without becoming difficult to release.
Re-check after change
A new phone, seat position, cable or storage habit can alter clearance. Revisit the installation whenever the use case changes, and remove any module that interferes with safe operation.