Applications in engineering could include down-borehole exploration; environmental monitoring where networks of sensor arrays could monitor subsurface water levels, or determine the location of landfill sites; tunnel detection; improved mapping of existing utility asset locations.
Existing gravimeters cost in excess of USD 100,000 and weigh more than 8kg. This device is similar to but a leap in the accuracy achieved by the type of accelerometer found in smart phones, which are relatively cheaply mass-produced. A smart phone is triggered by the acceleration due to the Earth, while the gravitational attraction from a nearby human could almost trigger this new device.
The full paper can be read in the scientific journal Nature: http://goo.gl/WnpPlA
