May 9 (Reuters) - The following are the top stories in the Wall Street Journal. Reuters has not verified these stories and does not vouch for their accuracy.
* Advertising giants Omnicom Group and Publicis Groupe have called off their $35 billion merger amid a variety of hurdles. "There was no finish line in sight and that created uncertainty," said Omnicom's CEO. (r.reuters.com/jus29v)
* As more young children get their pudgy hands on their parents' mobile devices, tech and toy industry entrepreneurs are feverishly cranking out apps and gadgets aimed at these digital-savvy youngsters. A side effect of this kiddo-market miniboom is a surge in product-testing sessions relying on tot testers. (r.reuters.com/kus29v)
* The European Central Bank sent an unusually strong signal Thursday that it would likely cut interest rates or take other stimulus measures at its June meeting to combat too-low inflation that threatens Europe's fitful recovery. (r.reuters.com/sus29v)
* Pfizer could cut its tax bill by hundreds of millions of dollars if it buys AstraZeneca, but thousands of Pfizer shareholders could face a tax hit if the deal goes through. The blow stems from a little-known provision of U.S. tax rules that is triggered when a U.S. company buys a firm overseas and relocates there to reduce its taxes. (r.reuters.com/qus29v)
* The U.S. economy is speeding ahead this quarter - perhaps growing faster than 4 percent - as the recovery gets back on track after a winter when growth slowed to a crawl, according to The Wall Street Journal's latest survey of economists. (r.reuters.com/tus29v)
* Mobile messaging app developer Snapchat has agreed to settle Federal Trade Commission charges that it deceived consumers about the disappearing nature of the messages sent through its service. (r.reuters.com/mus29v)
* RadioShack Corp is scrapping its plan to close as many as a quarter of its U.S. stores after it failed to reach an agreement with its lenders, dealing a blow to Chief Executive Joe Magnacca's overhaul of the consumer-electronics chain. (r.reuters.com/vus29v) (Compiled by Supriya Kurane in Bangalore)