OT - rechargeable virual debit card for phone?

Medical reasons: Mountain and Cave Rescue carry it (Entonox) to help relieve the pain for people with e.g. broken limbs on a long stretcher carry. e.g. the recent big rescue in South Wales

Not possible with the best smartphones.

Any FI's account with a debit card and no automatic overdraft will do that fine.

Irrelevant if what you care about is security.

Not even possible to ensure that.

And you are unlikely to lose it or have it stolen.

It's the grief of having to get a new phone and reloading it with all manner of stuff that worries me.

Are posters on the Nitrous oxide ?. Replies seem to be popping up in the wrong place ?

Yes, that would work fine. Anyone finding your phone couldn't make a purchase for more than the account balance - and only then, if they could get into the phone - which you would presumably lock with a PIN and/or fingerprint or face recognition.

You could top up the card from home from another account, using a desktop/laptop computer.

No grief at all with an iphone, just enter your apple id and carry on regardless.

snip.

On my Andriod with google pay you can make small purchases (eg £10-£15 in a cafe) without unlocking. You have to wake the screen up but not unlock it. I don't know how many of these you could make without ever actually unlocking the phone. (I assume whenever you do actually unlock it then the counter is reset to zero)

(This is the exact method I use using a chase account topped up from my main account via PC Internet banking. )