Researchers have developed a smartphone game that they say will help in a key battle against dementia - understanding how the brain navigates.

Sea Hero Quest, an adventure game in which players control ships and battle enemies, aims to become the world's biggest source of data about people's spatial awareness. Researchers say understanding how people navigate their surroundings is crucial to progress in dementia research.

The game, a joint project between scientists at University College London, the University of East Anglia, Deutsche Telekom and game designer Glitchers, represents an "unprecedented" scale of research, said Hilary Evans, the head of Alzheimer's Research UK said. "We have never seen anything undertaken in dementia research at this scale before," she added.