An app, called Plague Inc, where players aim to wipe out humanity with incurable diseases has increased rapidly in popularity during the Ebola outbreak and is now dominating the iPhone download charts.
The Smartphone game was designed by a British app designer and hit the number one spot for paid-for apps in the UK last week.
It has gained almost a million more players in the last two weeks as the spread of Ebola virus has claimed more victims.
The game is a strategy game, where players choose a virus to infect “patient zero”. The aim of the game is to “bring about the end of human history by evolving a deadly, global Plague whilst adapting against everything humanity can do to defend itself”.
A player wins “DNA points” as their virus spreads and is made stronger by mutating or becoming resistant to drugs.
Users are even allowed to customise their disease, with many now choosing to name it after the virus that has claimed more than 4,000 lives in West Africa.
The app, which costs 99p on the iPhone, was launched in 2012 by James Vaughan, who set up his company, Ndemic Creations, to design it.
He told the tech website Modojo that he designed the game because he “really wanted to play a mobile strategy game but could not find one.
“I realised there was a huge gap in the market and decided to fill it,” he said.
The number of players last week was nearly four million, an increase of more then 900,000 from two weeks before, according to MailOnline. “There will be people queuing up to say it’s a cash grab, and that couldn’t be further from the truth”, Mr Vaughan told the site.