This is a big deal. Apple and Google are combining their engineering prowess and dominant market positions to fight the coronavirus war in a smart and effective way. If successful, it may be the first step in turning the tide against the pandemic and moving society back to a more normal life.

On Friday, the two tech giants announced a joint effort to develop smartphone technology that can alert users if they have been in the proximity of an infected person. This capability, dubbed contact tracing, has shown to be effective in slowing the spread of the coronavirus by giving people timely information on whether they should self-quarantine or get tested.

When the plan is fully implemented, the two companies could potentially roll it out to a good chunk of the world’s population. Apple Inc.’s iOS and Google’s Android are used by about 3 billion people.