Izihlahla ezinkulu ze-oki zaseCalifornia ziye zagawulwa ngamakhulu ezinkulungwane ngenxa yesifo esabikwa okokuqala ngo-1995 futhi sabizwa ngokuthi “ukufa okuzumayo kwe-oki.” Ukuze bathole umbono obanzi ngalesi sifo, ososayensi base-UC Berkeley benze uhlelo lokusebenza lwe-smartphone ukuze abaqwali kanye nabanye abathandi bemvelo babike izihlahla abazithola zinqotshwe ukufa kungazelelwe.
Ukuze uthole ulwazi olwengeziwe mayelana nohlelo lokusebenza, ukuthi lwenzani nokuthi ungaluthola kanjani, vakashela OakMapper.org.