So why are smartphones the best devices to sit in a tree in the middle of the rainforest?
"The reason we're using phones is because we try to use what's already there," says White. "Hundreds of millions of phones are being thrown away around the world each year, which are ready to connect up to networks. The cellphone network is not great in these areas, but it's good enough for what we're trying to do."
It's not just the hardware that makes smartphones ideal for the job though. "Phones are great as they're the most popular development platform in the world.," says White. "It's such a robust ecosystem, and we're able to plug into that and make it work."
There's an app for that
The Guardians project has had about an unexpected benefit for Rainforest Connection: the charity now maintains live audio streams from rainforests around the globe.
White says: "What we essentially have is a real-time stream of really remote, crazy places around the world. We thought this was something people would want to listen in to, to show them that the rainforest is a really amazing place, but it's also a way for us to engage people in ways we haven't done before, and teach them more about what's going on."
Rainforest Connection aims to release an app for iOS and Android in the coming months that will enable you to listen in to different streams from rainforests around the world. It's more than just a live version of those Sounds of the Rainforest relaxation CDs, however: listeners will also be able to keep an ear out for the sounds of logging activity, wherever they're tuning in from.
"We want people to be able to hear the difference between a rainforest in Africa, Indonesia and Brazil, all right there at the touch of a button," says White. "If you want to use it to put your kid to sleep or as ambient noise, that's fine – but if you want to listen out for a chainsaw or a vehicle driving past, that would also be helpful."
What you can do to help
People around the world are concerned about the destruction of the rainforests, but they tend to see it as a problem for governments and charities, rather than one they can do something about themselves. Rainforest Connection is changing that – so how can people get involved?
To start with, you can donate that old phone that's buried at the bottom of a box of files. "The phones that go up in the trees don't have to be incredibly powerful," explains White. "They don't need big screens and stuff – we tend to use the older Android phones up there."
White says the most regularly used phones in the trees are the Huawei U8180, thanks to a big donation from a Chinese source. "The newer phones that people send in are incredibly useful as well, as we use them to equip the rangers," he adds.
"A lot of the rangers just receive SMS messages, but some have an app for Android and iOS that enables them to get notifications, see locations on a map and coordinate with other rangers to arrive at a logging site together."
Donating your phone isn't the only way in which you can help. If you're an experienced coder, charities such as Rainforest Connection could do with your time and expertise.
"We're looking for people who are interested in working on some fascinating problems," says White. "At the moment we're on a volunteer basis, and we want to find people who can use their Android skills in the forest with the Tembé warriors."
"Coding should be an adventure, not just from an intellectual standpoint but from a real life one as well. If you're looking for an adventure, get in touch."
So the next time you're disposing of your old smartphone, stop and think about what else it could do in another, very different life. Projects like Rainforest Connection can't stop the destruction of the rainforests overnight, but your phone could play a part – and it could even help to save lives. Visit the Rainforest Connection website to find out how.