Last Updated: Sunday, December 15, 2013, 15:23
Former Foursquare product head Alex Rainert came across Twitter's notification telling him that two of his friends were talking about 'Grey's Anatomy'.
Last Updated: Tuesday, November 19, 2013, 16:47
About 57 services including Police forces, London Fire Brigade, the Foreign Office and the Environment Agency have signed up for the Twitter Alerts that has been rolled out across the UK and Ireland.
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