Hi @Bathtime
Welcome welcome welcome 
Prices are shown in the currency of the country they trade, GDP in UK 
& USD in US 
When you click buy you’ll see a screen like this
Which shows the breakdown of all the costs.
Basically FT defaults everything to GBP where it can, the ethos from the founders is about long term wealth building and displaying your holdings in GBP helps with this. It is however a little contentious with many wishing to have other currency options.
If you’re new to the app / investing this thread might be worth scanning through.