Maybe I’m in the minority, but I always try my best to keep track of the number of hours I sleep per night. Somehow, knowing how many hours I slept the night before helps to justify, either personally or to others, my attentiveness — or lack thereof — on any given day.

“I’m not being very productive today,” I think to myself and then add the great reasoning: “It must be because I slept 15 minutes fewer than usual.”

However, “trying my best to keep track” really just means “keeping mental notes,” and we all know how unreliable those can be.

Even if you don’t keep track of how many hours you sleep or, frankly, don’t care, you should if you want to improve your sleep and be more productive.

Founded by three Brown University graduates, the Newton-based sleep management company Zeo released its second free sleep-tracking app Wednesday morning.

Sleep101, which is available in the iTunes app store, uses a new sleep data algorithm that “uses the accelerometer within iPhone smartphones as an entry-level sleep tracking device,” according to a press release.

In addition to tracking when you’re sleeping and awake, which can help point out sleeping issues, Sleep101 also provides a bunch of free, proven sleep advice with its library of “science-based advice, research papers and user success stories,” according to the release.

But here’s what I think is the best part of the app: It wakes you up at the optimal point of your morning sleep cycle and thus helps to reduce grogginess. I’m sold.

But if you’re still not convinced despite all these benefits, the app is “86.2 percent as accurate as wrist actigraphy, the clinically proven method for tracking sleep using wrist movement,” according to Zeo. Zeo also developed Sleep Manager, which is the leading and clinically proven sleep-tracking device in the world.

Plus, like Sigmund app developer Daniel Nadler, Zeo co-founder Jason Donahue is now studying as an MBA student at Harvard Business School. And given the success of that Harvard student’s dream app, Sleep101 is bound to do at least just as well…right?

Dave Dickinson, president and CEO of Zeo, is more convincing.

“Our Zeo Sleep Manager line is still the ultimate way to track your true sleep quality, including how much restorative REM and Deep sleep you get,” he said in the press release, “but our free Sleep101 app, which includes scientifically validated sleep advice, can be an important first step for anyone who wants to get a better night’s sleep.”

Hey, anything free that is also developed by geniuses to help the sleep deprived is worth a try.