No, I’m saying that the booking.com app, or the Skyscanner app or any of their competitors don’t support multiple tabs.

Their websites do (although even on new phones you are at a greater risc of a tab being purged and needing a reload, but still you can multi tab on the mobile website)

Ah the difference here is that I can't use multiple tabs on my phone as they are too small. So tabs are only relevant to me on desktops and even then I will often use new windows.