Instagram founders Kevin Systrom and Mike Krieger have reunited for their first launch since leaving Facebook, and they are coding for a cause.

Rt.live is a COVID19 tracker, focused on measuring a key statistic about how fast the virus is growing.

The value they track, Rt, is the average number of people infected by someone carrying the virus. If the Rt number is above 1 in any particular state, community spread is active and accelerating fast, so extra precautions are needed. If the number is below 1, it’s a positive sign that transmission is down and aggressive measures are starting to curb the growth.

You can see the state by state curves over a monthly timeline to help visualize the spread and get a more accurate picture on where things stand today.

Right now, Georgia has the highest Rt in the U.S. at a 1.5, whereas New York has dropped down to a 0.54 with a previous peak at 4.47. This data is extremely useful in understanding if stay-at-home orders are having an impact, and help inspire people to do their part.

As per TechCrunch, “Kevin has been writing and publishing open-source data analysis notebooks on how to calculate Rt on a daily basis. We wanted to take that work and visualize it so anyone can see how their state is doing at curbing the spread,” says founder, Krieger. You can check out their Rt.live modeling on Github.

This launch is quite a departure from the founders’ photography roots, but the virality they experienced at Instagram inspired them to apply concepts from growth modeling to the cause.

“As states decide whether and how to open back up, they’ll have to manage their infection rate carefully, and we hope dashboards like rt.live will be helpful in doing so” Krieger says. From

From symptom trackers, to trend watching, to crowdsourcing for a cure, we’ve seen some incredible products launch in the wake of COVID19.