Alongside tents and drinking water, RAF planes dropped more than 1,000 solar-powered lanterns attached to chargers for all types of mobile handsets to the stranded members of the Yazidi religious community below.
It is the first time the lanterns have been airdropped in such a relief effort, but humanitarian workers say it is part of growing efforts to develop technology designed to make a difference in disaster zones.
In 2010, Dr Paul Gardner-Stephen, a computer systems researcher at Flinders University in Australia, was driving to work in his car when he first heard radio reports of the devastation of the Haiti earthquake, more than 10,000 miles away.
With roads blocked, infrastructure reduced to rubble and mobile networks down, he realised something needed to be done, and quickly.
"You typically have about three days to restore the communications before the bad people realise the good people aren't in control any more," he says.
His solution was to develop the technology that allows mobile phones to communicate directly with each other even where there is no network coverage, or when mobile masts have been knocked out of action - a system known as "mesh networking".
His Serval Project work means users can send text messages, make calls and send files to otherusers nearby, creating a mobile network through a web of users.
By Edwin Lane
Technology reporter, BBC News
How technology
is changing
disaster relief
When the British government delivered emergency aid to people fleeing Islamic militants in northern Iraq last month, one of its primary concerns was how the refugees might charge their mobile phones.