Now that Nest has resumed selling the Protect smoke detector following a recall, it's back to business as usual: The company needs to make sure this isn't just a safer product, but a better one. The Google-owned firm just released a fairly meaty software update, with features that run the gamut from finer user controls to improved accuracy. Most importantly, perhaps, the Protect now claims to do a better job telling the difference between steam and smoke, with the so-called Steam Check feature reducing those kinds of false alarms by 50 percent. Meanwhile, a new "Safety History" shows you a 10-day log of what caused your alarm to go off. Included in that record are carbon monoxide levels, including how long they were in dangerously high territory.