About 211 of the great apes are estimated to be living in the park
A mobile phone application has been launched to help protect the critically endangered mountain gorillas in the Democratic Republic of Congo.
The app, called iGorilla, allows users of iPhones and iPads to follow the lives of gorilla families in the remote forests of the Virunga National Park.
Each app costs $4 (£3), with most of the money going to the park.
The mountain gorilla population has been reduced by poaching, civil conflict, deforestation and disease.
But conservation work is helping to secure the remaining 720 animals, with an estimated 211 of the great apes living in the park.
The new app, launched by the Virunga National Park, allows users to choose a gorilla family, find out about individual members and follow their lives through reports, photographs and videos.
The park straddles the Democratic Republic of Congo, Rwanda and Uganda, covering 7,800 sq km (3,000 sq miles).
It was declared a Unesco World Heritage Site in 1979.