Booking.com tablet to mobile: retire a legacy stack without hurting conversion
UX Designer, 2020–2021. Tablet had its own legacy site with bugs, legal issues, and shrinking usage. I self-started a project to deprecate that codebase and run tablet on the mobile stack. I built the business case, aligned stakeholders, recruited developers, and led the migration with a strict “no tablet-only components” rule.
Problem
Maintaining a separate tablet stack slowed delivery and increased risk. Tablet traffic was down 8.5% year over year. Early tests showed the mobile layout did not translate well to larger screens. Conversion on tablet lagged and key interactions dropped, so a straight swap risked making outcomes worse.
Solution
Replace the tablet site with the existing mobile experience, then close gaps with targeted experiments. I partnered with engineering to add analytics for filterable events like room selection and map interactions. We ran multi-variant A/B tests and shipped in small iterations, tuning layout density, tap targets, and control placement for larger screens. We kept everything within the mobile design system to eliminate rework and avoid new maintenance debt.
Impact
Conversion moved from a −2.5% drop to −0.83% versus control, while core behaviors improved. Room selection increased 17% and map usage rose 161%. The tablet codebase was fully deprecated, freeing four teams’ roadmaps, and all future mobile updates now apply to tablet by default. Legal compliance issues were resolved as part of the migration. We measured success through experiment results and new analytics events tied to conversion, room selection, and map usage, and we documented the trade-offs so the business could make an informed call on rollout.
What I learned
Progress can mean removing what is broken, not adding more. Targeted cleanup reduces risk, lowers costs, and improves outcomes.