So just back from Lidl. There's a small scanner at the till behind the perspex screen so you have to poke your phone through the not quite big enough hole to get it to scan your card. So far so good.
However I don't understand how they're applying the coupons. I had two activated, the €5 off if you spent €25 or more and the cookies for €1 instead of €2. I spent €63 so you'd expect me to have saved €6, right? Wrong!
The one for the cookies didn't work at all, and rather than simply deducting €5 from the total bill at the end as you would assume, it applied a discount to each and every item of about 7.5%.
Total savings were €5.36 in the end.
It says it will give an error if you try to activate two vouchers that can't be combined.