Satellite tracking technology is used in everything from smartphones to smart watches - gadgets that can tell you where you are, how fast you are moving and even what kind of activities you are busy with throughout the day. They collect this surprising amount of data from built-in miniature sensors. These devices are getting more powerful but nevertheless smaller, lighter and easier to use every year. This rapidly advancing technology is now available for ecologists who want to know more about the behaviour and movements of the wild animals they study. Using technology similar to smartphones and smart watches, ecologists can now almost continuously monitor their study animals' geographic location, behaviour, activity and body temperature. At the same time the device collects information about the area the animal is moving in, including air temperature, atmospheric pressure and water salinity. This not only provides insights into ecology but also into the weather, climate, atmosphere, natural catastrophes (e.g. earthquakes and tsunamis) and outbreaks of diseases, all of which may change animal behaviour. This new technology with its myriad of different applications has heralded the start of a golden age for "bio-logging" – a term scientists have coined for logging large amounts of biological data.