Sometimes you happen to swipe the wrong item whilst you are shopping. No problem, in Grosh the grocery item stays in the list until you swipe the next one or leave the shopping list screen, giving you time to undo the action after the mistake. A bought item is marked with a green bar to the left and with strike-through font. To undo, just right swipe the item again (just like you did when marking it as purchased). That will mark the item orange again and with normal font.
PS If you want to undo multiple purchases, 2 finger swipe to the green screen and tap the grocery trip you want to modify. Then left swipe the items you want to move back to the grocery list.
