In an article for Cnet this week, Nate Lanxon said the Prenvo Mobile Allowance for iPhone software is "very fast" and is a simple way of checking where your balance is up to.
He explained at 59p, users should not expect a multifunction application, but added the one job that the widget performs is enough to give it a recommendation.
One site contributor added to the piece: "Why this isn’t on every phone made by every company, everywhere, ever, is a mystery."
Compatible with the very latest Apple iPhone 3G S, the product can be purchased and installed quickly and easily via a quick visit to the App Store.
On reviewing the handset itself earlier this year, Flora Graham said in a piece for the site that the gadget offered a level of usability that was so far "unrivalled".
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