to say google discontinued a project after a short period of time does not exactly speak to the level of difficulty or if that difficulty was even the reasoning for the discontinuing. someone at G could have just gotten bored or moved to a different department, or a new darling employee stole focus, or whatever other reasonings we've heard when G projects are shuttered.

> the program was discontinued in 2018

To be fair, the Verily folks did design the algorithm that predicts where your blood sugar will be in X minutes in Dexcom CGMs, which lives on. Dexcom now owns the patent.

> nothing beats an actual blood sample

Technically, interstitial fluid can get you pretty dang close, which is considered minimally invasive.

Nothing beats a blood sample, but interstitial fluid (which is invasive kind of) is good enough for insulin dosing. Most CGMs (Dexcom, Freestyle, etc) work this way. They don't sample blood, they sample the fluid between cells.