Yahoo Inc will buy mobile analytics startup Flurry to beef up a fast-growing mobile advertising business that still lags Google Incs and Facebook Incs in scale. Six-year-old Flurry uses analytics to help target ads at consumers by monitoring activity on more than half a million apps on some 1.4 billion mobile devices around the world, Yahoo said in a statement on Monday. The startup provides information to help marketers and brands more easily reach their desired audiences, Yahoo said. Yahoo did not cite a price tag, but a source familiar with the matter said the Internet company is paying several hundred million dollars.