Value4Money calculates best value for money when comparing like products, eg a 300 gram tin of coffee or 100 gram packet - which is better value?. Value4Money lets you compare up to three items and highlights, in green (the color of money), which item gives more for your money.
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Compare like with like eg. grams with grams. A conversion tool is also provided with Value4Money if required.
An android application for Value4Money is also available.
You can find details here.