Mobile technology had the biggest benefit of all technology on aid operations in 2019, according to an exclusive poll by the Thomson Reuters Foundation on Wednesday, with drones and satellites also helping to speed up help to people in need.

From drones delivering children’s vaccines in Vanuatu to satellite early warning systems in Africa’s drought-ravaged Sahel, technology is revolutionizing aid operations.

Humanitarian groups said new tech had helped them respond to disasters quicker in 2019, assess needs more accurately, reach far-flung communities and mitigate potential risks.

The U.N. children’s agency UNICEF said drones held great promise for delivering medical supplies to rural areas and responding to disasters like earthquakes and floods, with their potential being explored from Namibia to Kazakhstan.

Sierra Leone launched a drone testing corridor last month, with UNICEF’s support, while Malawi will open Africa’s first drone and data academy next year to train drone pilots and data scientists.

But most of the 18 agencies polled between Nov. 25 and Dec. 8 said mobile technology had brought the biggest benefits to the people they were helping.

“The increased global access to mobile devices has had a massive impact on the humanitarian world,” said the Danish Refugee Council’s Christian Gad.

With more than five billion people globally now having mobile phones, this allows people caught up in crises to get vital information for staying safe, keep track of loved-ones, access services and receive cash transfers.

The United Nations’ Food and Agriculture Organization (FAO) described mobile banking as “a real game-changer”.

In Somalia, it is pioneering a phone-based system allowing money to be sent directly to participants in livelihood protection programs.

“This avoids a raft of challenges we’ve long faced in getting cash to remote parts and safely into people’s hands so they can buy food locally and avoid selling off assets to get through lean times,” said the FAO’s Dominique Burgeon.

Mercy Corps said “bundled mobile services” providing multiple tools and resources in one place had been a huge boon.

In east Africa, it has provided more than 3 million farmers with apps aggregating information on everything from weather forecasts to livestock market prices to help them boost harvests and incomes.

For millions caught up in crises, electronic voucher cards give families the freedom to buy what they need, while supporting the local economy.

In Bangladesh, the World Food Programme has given cards to more than 200,000 Rohingya refugee families. Fingerprint verification is embedded in the cards to ensure people receive their correct entitlement and prevent fraud.

World Vision also pointed to the use of biometric technology in Ebola vaccine trials in Sierra Leone where hand-held tablets with iris-scanning cameras help ensure participants get the right doses and deter impersonation.

Other agencies including CARE said open-source tools that can be used with mobiles were transforming the collection and processing of information in disasters, replacing cumbersome paper-based assessments.

This speeds up decision making, allowing humanitarian workers to get aid to the worst hit places faster and respond quickly to changing needs.

Agencies are also using technology to collect feedback remotely from communities receiving assistance.

“I’m most excited about the technologies … that focus on giving the people we work with a greater voice and the ability to hold us to account better,” said Oxfam GB’s Danny Sriskandarajah.

International Medical Corps said innovative software was also transforming what is known as “the last mile”, helping streamline pharmaceutical supply chains and slash delivery times to hard-to-reach places.

Technology is not only helping aid agencies respond to disasters, but to mitigate them.

Action Against Hunger has created a Pastoral Early Warning System which uses satellite data to track droughts and anticipate risks in the semi-arid Sahel which skirts the Sahara.

The data enables the agency to measure plant growth and surface water across the 4,000 km (2,485 miles) Sahel.

“To have such a phenomenal level of information is totally transforming how we plan for and respond to crises,” said Action Against Hunger’s Marie-Julie Lambert.

“This year, we already know that vegetation levels in Senegal and Mauritania are alarmingly low. Without this technology we wouldn’t have been able to predict the sheer scale of the looming crisis.”

Several organizations highlighted how tech was helping empower and protect girls and women.

Plan International is rolling out a social media platform called Girls Out Loud providing a safe, private space to discuss topics like sexual health and gender violence.

In Jordan, ActionAid UK is working on an app to help refugee women access services, while in Vietnam it has developed a Safe City app enabling users to mark safe and unsafe locations, find the most secure routes, sound an alarm and make emergency calls.