On Monday, 8 July 2019 14:27:46 UTC+1, T i m wrote:
A simple / clear real-time usage display (ideally in a tangible form
like kWh, not just 'None - Loads') and if it could also manage the
current running 'cost', plus possibly the cumulative cost, that might
be the cherry on the cake, especially if the total could also include
a daily standing charge?

I think the British Gas Minim monitors they gave away as part of a greenwash scheme a decade ago would do this, but they're known for not being terribly accurate. I don't think anything that clamps rounfd the meter tail is particularly accurate.

They and similar appear on ebay for reasonable values of peanuts.

p.s. Am I right in thinking this is one of (/only?) the 'perks' of
getting a smart meter fitted, the remote display thing?

Yes. But I don't know if they show you how much credit is remaining on a prepayment meter. It would be a bit useless if they didn't, but I've got used to things being a bit useless.

Owain