According to AppLift, travel currently represents 5% of all apps on the App Store. And their cost of aquisition ranges from US$ 1.10 in Germany to US$ 3.00 in the US. Interesting is also, that you wont find Booking.com and Expedia among the top 5 travel apps per country, and TripAdvisor only in the UK. Get the full infographic at SlideShare