Unilever is harnessing mobile advertising to launch a £2m campaign for the new Rich Beef Stock Pot from Knorr. Fronted by Marco Pierre White, the above-the-line push runs from next month. Unilever said it would reach millions of iPhone and iPod touch users. The variant, launched in October, is stronger than the standard and would appeal to consumers looking for a beefier roast, the company said.