Technology is changing the world around us.
From the recent protests in Turkey to the Arab Spring and the Occupy movement, technological innovations are opening up new ways for the human race to come together and demand change.
This has huge potential across the developing world - but it's crucial that girls are involved in this technological revolution. This year's G(irls)20 Summit, which takes place in Moscow next week, will focus on making sure that happens.
You can help too, by showing your support for the Girl Declaration and calling on the international community to invest in opportunities for girls. Here are three of our favourite tech innovations that show why empowering girls should be a priority…
1. Safe Pregnancy and Birth
Mobile app Safe Pregnancy and Birth is a condensed version of the medical textbook Where There Is No Doctor. Created by Hesperian Health Guides, it breaks a 600-page book down into a 100-screen app and has already been downloaded more than 24,000 times in 155 countries. Girls, women and healthcare workers can use it to access accurate (and often culturally sensitive) health information, which is in short supply for many girls.
"Girls can now take control of their own health - and take ownership of new digital technologies," says project co-ordinator Zena Herman.
Violence against girls and women is widespread in the favelas of Rio de Janeiro, restricting girls' chances of getting a full education and a job in later life. The SmartWomen website and app encourages girls to take photos and videos of safety risks, such as lack of lighting and obscured walking routes. These contributions are used to create interactive digital maps of the favelas, which are published online alongside information including useful contacts for support services.
"When violence occurs, we have to ensure that she finds the necessary support and services to deal with the situation and protect herself so that it doesn't happen again," says Luciana Phebo, Unicef co-ordinator in Rio de Janeiro.
Adolescent girls are often relied on for chores such as fetching water and collecting firewood (used to boil the water for purification). Meeting these familial expectations can result in young girls such as nine-year-old Anzelma missing school to walk for miles to bring firewood back: a time-consuming and potentially dangerous task, with many girls reporting experiences of sexual violence during the journey.
LifeStraw is a high-tech water filter that removes 99.99 per cent of bacteria and viruses. Once fitted to a tap or water pump, it can be used by a family of five for three years. As well as significantly reducing waterborne illnesses, the technology has revolutionised life for Kenyan girls: with no need for firewood collecting, they are able to use that precious time to go to school, gain an education and acquire the skills they need to get a job.
"This programme is a direct investment in public health, women and girls, and the future of Kenya," says Mikkel Vestergaard Frandsen from LifeStraw.
Over the next few days G(irls)20 will bring even more innovations, ideas and projects such as these to the world's attention. We can't wait to see how they're going to power the girl effect.
Show your support for the Girl Declaration
Follow our live coverage of G(irls)20 on Twitter using #girls2015
Find out more about the G(irls)20 Summit
Do you know a great girl tech innovation that's making the girl effect happen? Tell us about it on Twitter and Facebook