Life

This tweet about PGA perfectly shows how smartphones have changed our lives

Tiger Woods plays at the 2018 PGA Championship at Bellerive Country Club on August 12, 2018 in St Louis, Missouri. 
Richard Heathcote | Getty Images
Tiger Woods plays at the 2018 PGA Championship at Bellerive Country Club on August 12, 2018 in St Louis, Missouri. 

On August 8, as Tiger Woods played this year's 2018 PGA Championship in St Louis, Missouri, not every eye was on him. One Twitter user was looking at the crowds.

Jamie Kennedy, who in his Twitter profile identifies himself as content director for The European Tour and Ryder Cup Europe, tweeted a photo comparing the crowds watching Tiger Woods play in 2002 versus 2018. The difference? Sixteen years ago the spectators were just watching Woods; now they're nearly all filming the action via their smartphones.

It's a perfect illustration of one of the ways smartphones have changed our lives.

"Most people check their phone every 15 minutes or less, even if they have no alerts or notifications," Larry Rosen, psychology professor and author of The Distracted Mind, tells CNBC.

The vast majority of Americans have a cellphone, and 77 percent own Smartphones, according to PEW Research, which is up 35 percent since just 2011.

Here's a look at how people had experiences before Smartphones — and how they do it now.

Sporting events

As Kennedy pointed out via Twitter, when Tiger Woods played in the early 2000s (before the iPhone was released in 2007), as he did at Target World Challenge on December 11, 2005 at the Sherwood Country Club in Thousand Oaks, California, fans watched.

Tiger Woods playing the Target World Challenge on December 11, 2005 at the Sherwood Country Club in Thousand Oaks, California.
Jeff Gross | Getty Images
Tiger Woods playing the Target World Challenge on December 11, 2005 at the Sherwood Country Club in Thousand Oaks, California.

Many more golf lovers shot Woods playing golf at the 2018 PGA Championship in August in St Louis via their smartphones.

Tiger Woods plays at the 2018 PGA Championship at Bellerive Country Club on August 12, 2018 in St Louis, Missouri. 
Richard Heathcote | Getty Images
Tiger Woods plays at the 2018 PGA Championship at Bellerive Country Club on August 12, 2018 in St Louis, Missouri. 

Restaurants

Before smartphones, diners would look at each other and have conversations, as these two did in 2003 over McDonald's.

People used to talk to each other when they ate pre-smartphones. Here, two guys eat at a McDonalds restaurant on November 27, 2003 in London. 
Graeme Robertson | Getty Images News | Getty Images
People used to talk to each other when they ate pre-smartphones. Here, two guys eat at a McDonalds restaurant on November 27, 2003 in London. 

Now it's often just as much about the smartphone as it is the company. Diners at Peruvian restuarant at Chalan on the Beach in Miami, Forida, sit looking at their smartphones in 2014.

Diners at Chalan on the Beach restaurant in Miami, Florida, on their phones in 2014.
Jeff Greenberg | Getty Images
Diners at Chalan on the Beach restaurant in Miami, Florida, on their phones in 2014.

Plus, you have to take a picture of it before you eat it, like this man taking a selfie with his tapas in 2018.

Taking a food selfie in Madrid, Spain in 2018
Anadolu Agency | Getty Images
Taking a food selfie in Madrid, Spain in 2018

Tourist attractions

Before smartphones, tourists would just gaze at the attraction and then ask a bystander to snap a photo of them in front of it, as members of the National Youth Theatre may have done in Red Square in Moscow, Russia, in 1989. (Source: Georges De Keerle/Getty)

Now tourists take selfies, like these travelers at Red Square in Moscow in July 2018.

Tourists take photos and selfies at Red Square in Moscow on July 14, 2018. 
Jewel Samad
Tourists take photos and selfies at Red Square in Moscow on July 14, 2018. 

Celebrities

Actors used to give fans autographs, as Will Smith did in Times Square in Manhattan, New York in 1999.

Will Smith at MTV's 'TRL' on October 31, 1999 at MTV Studios in Times Square in New York City, New York.
KMazur | Getty Images
Will Smith at MTV's 'TRL' on October 31, 1999 at MTV Studios in Times Square in New York City, New York.

Now, they take selfies with stars like Henry Cavill, here at Paramount Pictures' "Mission: Impossible Fallout" premiere in Washington D.C. in July 2018.

Actor Henry Cavill who plays "August Walker" in Mission: Impossible Fallout, takes selfies with fans, on the red carpet of the U.S. premiere at the Smithsonian National Air and Space Museum in Washington, D.C., on Sunday, July 22, 2018.
NurPhoto | Getty Images
Actor Henry Cavill who plays "August Walker" in Mission: Impossible Fallout, takes selfies with fans, on the red carpet of the U.S. premiere at the Smithsonian National Air and Space Museum in Washington, D.C., on Sunday, July 22, 2018.

Concerts

Before Smartphones, people would hold up lighters during songs they loved at concerts, like fans did here, circa 2000.

People holding lighters at a concert circa 2000.
Michael Linssen | Getty Images
People holding lighters at a concert circa 2000.

Now concert-goers light up the stadium with sartphones, like they did in July 2017 during a U2 concert in Paris.

People hold up their mobile phones to film events on stage during a concert by Irish rock band U2 at the Stade de France in Saint-Denis, outside Paris, on July 25, 2017.
AFP | Getty Images
People hold up their mobile phones to film events on stage during a concert by Irish rock band U2 at the Stade de France in Saint-Denis, outside Paris, on July 25, 2017.