Beer-fuelled iPhone apps are creating hangovers in the business world with lawsuits filed between the companies offering the "iBeer" and "iPint" applications.

Molson Coors Brewing and ad co Beattie McGuinness Bungay face a $12.5m (£7.1m) lawsuit for allegedly pinching the novelty iPhone app.

iPhone application creator Hottrix is suing the brewer and ad agency for apparently ripping off its "iBeer" iPhone application and creating their own version for Carling called "iPint".

Beattie McGuinness Bungay were said to have been in talks with Hottrix to use their tech, that takes advanatge of the iPhone's accelerometer, but then created its own rival (and free) version - iPint - with another developer Illusion Labs.

The lawsuit said: "As iPint increased in popularity, iBeer 2.0 decreased in popularity since end users could get ostensibly the same application without a direct cost - besides viewing the Carling advertising - of paying $2.99 for iBeer 2.0".

iPint has been removed from the Apple store in the US, but remains available for download internationally.