The executive provided more color on the number on his company's Google+ social networking service.
"For those wondering, we count each device only once (ie, we don't count re-sold devices), and "activations" means you go into a store, buy a device, put it on the network by subscribing to a wireless service."
Rubin's announcement follows an update from a quarterly earnings call in July when Google touted a new figure of 550,000. In June, Rubin announced that activations had topped 500,000 a day and were growing at a rate of 4.4 percent per week.
Android growth appeared to have tapered off some, as the platform's growth rate in June and July would have presumably pushed the platform past the 700,000 per day mark by the end of September.
Regardless, Google has seen substantial growth in Android's user base this year. Recent figures from The NPD Group show that Android-based smartphones represented a 53 percent share of the market from the beginning of the year to the end of October. By comparison, Apple's iPhone held 29 percent.
At least for now, Apple is maintaining a sizable lead on Android in the tablet market. IDC reports that the iPad held a 61.5 percent share of the tablet market in the third quarter. However, with the addition of sales of Amazon's Kindle Fire in the fourth quarter, the iPad is expected to drop to 59 percent market share.
As Google has widened its lead on Apple, the iPhone maker has declined to continue updating its activation numbers. The most recent figure comes from last October, when late Apple co-founder Steve Jobs revealed that iOS activations stood at 275,000 on average per day. CEO Tim Cook did, however, say that cumulative iOS sales topped 250 million devices during the most recent September quarter.