The Roll

Opens straight away. Add it to your home screen and it lives on your phone like any other app.

Say it. See it. Tear it off.

Hold one button and talk. Two gallons of milk, paper towels, chicken thighs, and all three are on the list before you have put the phone down. It hears you on your own machine, so it works with no signal.

Crossing something off is tearing it off. The row drops to paper, sits a degree askew with a torn edge, and there is an undo button sitting right there when you get it wrong.

Then the part it is proud of. It takes that one list and prices it at every shop near you, side by side, and tells you how much of your list each one could actually price. A shop that only found three of your twelve things does not get to look like the cheapest.

It scans barcodes with the camera, reads your receipt afterwards so it learns what things really cost where you really shop, and hunts the week's sales on anything still sitting on the list. It never tells you a coupon is clipped unless something actually got clipped.