When it hears a T3/T4 type alarm sound from regular non-connected smoke/co alarms, it will notify you and/or others with a push notification. Also has an IFTTT Chanel. Reg $50
2 Likes
Back to $45. 
From Amazon they are still only $30, but backordered for 2-4 weeks. 3rd party sellers are in stock and $45-$50+