Angry stoners are becoming increasingly confused over iPhone app Herb Converter.

The app was created to perform simple calculations, such as cutting ounces of the illegal plant into grams and multiplying weight by price.

However, some doped-out customers want the app to physically weigh the weed – as if iPhones were now drug scales. Until this capability was included, one wrote on the US iTunes site, “ITS A FRAUD APP!!!!”

Another couple of tokers was left miffed the app did not take into account different strains and quality of the drug when deducing prices.

“Why only one price when there are so many varieties of pot,” one wrote.

“Bro I like ur app,” said another , “but it needs to say the… name if all the weed… if ur kool.”

Other requests from THC fiends includes “removing the useless dictionary,” support for joints and blunts, and traditional, street-style rounding down of ounces to grams so no one gets stabbed (“outside a lab, these numbers are wrong”).

Itunes also offers an app telling 420 friendly people where to score the drug in America. However, ‘Cannabis’ does relate to the country’s medical marijuana clinics. Thirteen states offer medical marijuana and users must have a card/ orescription to indulge/ medicate themselves.