One API, two front ends
Repair status, estimates and history should come from one service layer. When the site and the app read the same endpoints, customers who prefer a browser get the same truth as those on mobile — with no duplicated business logic to drift.
Design tokens travel
A shared token set — colour, type scale, spacing, component behaviour — means a change in brand ships to both surfaces in one pass instead of two redesigns a year apart.
The site is the acquisition layer
Location pages, service detail pages and a fast booking flow are what bring people to the point where installing the app makes sense. Build them together and the funnel stops leaking between them.