Tomorrow's shoppers could be doing price checks on their own phones, MPs have heard.
A bill tabled in the House of Commons today would see supermarkets made to publish prices online so shoppers can check they get the best deal.
Labour MP John Denham said his aim with the bill was simple.
"Barely a day goes by without someone in the House saying that times are tough for hard-working families.
"For many, the weekly supermarket bill - about 16 per cent of family spending on average, but much bigger for many low-income families - is one of the largest single parts of family spending.
"No one has money to waste. Shoppers want to know that they are getting the best value for money for their hard-won pounds," he said.
The member for Southampton and Itchen said there was no reason to believe it would impose a burden as prices were clearly publicly available and supermarkets constantly collated the data.
The trick was simply posting the data online using a common application that web developers could incorporate into their own programs.
Entrepreneurs could then cross-reference the data on a single smartphone app or website, he said.
"As smartphones and consumer apps grow in availability and popularity, the supermarkets will not be able to ask, 'Why should we do this?' They will have to explain why they have not done it," he said.
Fellow Labour MPs Alan Whitehead, Nick Raynsford, Paul Blomfield, the Liberal Democrats' Lorely Burt, Plaid Cymru's Jonathan Edwards, the Tories' Justin Tomlinson and the Greens' Caroline Lucas also backed the bill. It will see its second reading in February.
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