Well, at xmr.to:

> We can recommend Monerujo on Android and Cake Wallet on iOS. These wallets integrate natively with XMR.to.

I don't use either Android or iOS.

Do you recommend a suitable Linux wallet?

Just use the official Monero wallet, the only difference is that you'll need to visit xmr.to to enter the Bitcoin address you want to pay to instead of doing it in-app.

OK, thanks.