Songs that topped at least for at least one second with one version, the version being at #1 on iTunes (except for those that were #1 thanks to the Pre-Order Effect):

2 Chainz & Wiz Khalifa - "We Own It (Fast & Furious)"
5 Seconds Of Summer - "Don't Stop"
5 Seconds Of Summer - "Fly Away"
5 Seconds Of Summer - "Kiss Me Kiss Me"
5 Seconds Of Summer - "She's Kinda Hot"
50 Cent - "Candy Shop (feat. Olivia)"
50 Cent - "My Life (feat. Eminem & Adam Levine)"
A Great Big World & Christina Aguilera - "Say Something"
Adam Wakefield - "Lonesome Broken and Blue (The Voice Performance)"
Adele - "Hello"
Adele - "Rolling In The Deep"
Adele - "Set Fire To The Rain"
Adele - "Skyfall"
Adele - "Someone Like You"
Akon - "I Wanna **** You (feat. Snoop Dogg)"
Akon - "Smack That (feat. Eminem)"
Akon - "Sorry, Blame It On Me"
Alex & Sierra - "Gravity (The X Factor USA Performance)"
Alex & Sierra - "Say Something (The X Factor USA Performance)"
Alicia Keys - "No One"
Ariana Grande - "Break Free (feat. Zedd)"
Ariana Grande - "Dangerous Woman"
Ariana Grande - "Problem (feat. Iggy Azalea)"
Ariana Grande - "The Way (feat. Mac Miller)"
Artists Of Then, Now & Forever - "Forever Country"
Artists For Haiti - "We Are The World 25 For Haiti"
Ashlee Simpson - "Invisible"
Avril Lavigne - "Girlfriend"
B.o.B - "Nothin' On You (feat. Bruno Mars)"
B.o.B - "Strange Clouds (feat. Lil Wayne)"
Baauer - "Harlem Shake"
Beyoncé - "Beautiful Liar (feat. Shakira)"
Beyoncé - "Check On It (feat. Slim Thug & Bun B)"
Beyoncé - "Crazy In Love (feat. Jay-Z)"
Beyoncé - "Formation"
Beyoncé - "If I Were A Boy"
Beyoncé - "Irreplaceable"
Beyoncé - "Single Ladies (Put A Ring On It)"
Billy Gilman - "I Surrender (The Voice Performance)"
Blake Shelton - "Came Here To Forget"
Bowling for Soup - "1985"
Britney Spears - "3"
Britney Spears - "Circus"
Britney Spears - "Gimme More"
Britney Spears - "Hold It Against Me"
Britney Spears - "Make Me... (feat. G-Eazy)"
Britney Spears - "Till The World Ends"
Britney Spears - "Toxic"
Britney Spears - "Womanizer"
Broadway For Orlando - "What the World Needs Now Is Love"
Bruno Mars - "24K Magic"
Bruno Mars - "Grenade"
Bruno Mars - "It Will Rain"
Bruno Mars - "Just The Way You Are"
Bruno Mars - "Locked Out Of Heaven"
Bruno Mars - "When I Was Your Man"
Calvin Harris - "This Is What You Came For (feat. Rihanna)"
Carly Rae Jepsen - "Call Me Maybe"
Cassadee Pope - "Cry (The Voice Performance)"
Cassadee Pope - "Over You (The Voice Performance)"
Cassadee Pope - "Stupid Boy (The Voice Performance)"
Chris Brown - "Kiss Kiss (feat. T-Pain)"
Colbie Caillat - "Bubbly"
Colbie Caillay - "I Do"
Coldplay - "Viva la Vida"
D12 - "My Band"
D4L - "Laffy Taffy"
Daft Punk - "Get Lucky (Radio Edit) [feat. Pharrell Williams]"
Daniel Powter - "Bad Day"
David Archuleta - "Crush"
David Cook - "The Time Of My Life"
David Guetta - "Turn Me On (feat. Nicki Minaj)"
Demi Lovato - "Cool For the Summer"
Demi Lovato - "Heart Attack"
Demi Lovato - "Skyscraper"
Demi Lovato & Joe Jonas - "This Is Me"
Destiny's Child - "Lose My Breath"
Dia Frampton - "Inventing Shadows (The Voice Performance)"
Dixie Chicks - "Not Ready To Make Nice"
DJ Khaled - "For Free (feat. Drake)"
DJ Snake - "Let Me Love You (feat. Justin Bieber)"
Dr. Dre - "I Need A Doctor (feat. Eminem & Skylar Grey)"
Drake - "Fake Love"
Drake - "Forever (feat. Kanye West, Lil Wayne & Eminem)"
Drake - "Hotline Bling"
Drake - "Make Me Proud (feat. Nicki Minaj)"
Drake - "One Dance (feat. Wizkid & Kyla)"
Drake - "Pop Style (feat. The Throne)"
Drake - "Summer Sixteen"
Drake - "Take Care (feat. Rihanna)"
Ed Sheeran - "Afire Love"
Ed Sheeran - "Thinking Out Loud"
Ellie Goulding - "Love Me Like You Do (From "Fifty Shades of Grey")"
Eminem - "Berzerk"
Eminem - "Crack A Bottle (feat. Dr. Dre & 50 Cent)"
Eminem - "Just Lose It"
Eminem - "Love The Way You Lie (feat. Rihanna)"
Eminem - "Not Afraid"
Eminem - "Rap God"
Eminem - "The Monster (feat. Rihanna)"
Eminem - "When I'm Gone"
Fall Out Boy - "This Ain't A Scene, It's An Arms Race"
Far East Movement - "Like A G6 (feat. The Cataracs & Dev)"
Fergie - "Fergalicious (feat. will.i.am)"
Fergie - "Glamorous (feat. Ludacris)"
Fergie - "London Bridge"
Fetty Wap - "My Way (feat. Monty)"
Flo Rida - "Low (feat. T-Pain)"
Flo Rida - "My House"
Flo Rida - "Right Round (feat. Ke$ha)"
Flo Rida - "Whistle"
Florida Georgia Line - "Dirt"
Foster The People - "Pumped Up Kicks"
Fun. - "We Are Young (feat. Janelle Monáe)"
Glee Cast - "Don't Stop Believin' (Glee Cast Version)"
Glee Cast - "Empire State Of Mind (Glee Cast Version)"
Glee Cast - "Firework (Glee Cast Version)"
Glee Cast - "Forget You (Glee Cast Version) [feat. Gwyneth Paltrow]"
Glee Cast - "Loser Like Me (Glee Cast Version)"
Glee Cast - "Rumour Has It / Someone Like You (Glee Cast Version)"
Glee Cast - "Teenage Dream (Glee Cast Version)"
Glee Cast - "Toxic (Glee Cast Version)"
Glee Cast - "We Are Young (Glee Cast Version)"
Glee Cast - "Without You (Glee Cast Version)"
Gnarls Barkley - "Crazy"
Gotye - "Somebody That I Used To Know (feat. Kimbra)"
Green Day - "Boulevard of Broken Dreams"
Gwen Stefani - "Hollaback Girl"
Gwen Stefani - "The Sweet Escape (feat. Akon)"
Hannah Montana - "He Could Be The One"
High School Musical Cast - "Breaking Free"
Hinder - "Lips Of An Angel"
Hoobastank - "The Reason"
Iggy Azalea - "Fancy (feat. Charli XCX)"
James Blunt - "You're Beautiful"
Jason Aldean - "Burnin' It Down"
Jason Aldean - "Take A Little Ride"
Jason Mraz - "I Won't Give Up"
Javier Colon - "Stitch By Stitch (The Voice Performance)"
Jay-Z - "Empire State Of Mind (feat. Alicia Keys)"
Jay-Z & Linkin Park - "Numb / Encore"
Jay-Z, Bono, The Edge & Rihanna - "Stranded (Haiti Mon Amour)"
Jeff Buckley - "Hallelujah"
Jennifer Lopez - "On The Floor (feat. Pitbull)"
Jessica Simpson - "These Boots Are Made For Walkin'"
Jessie J, Ariana Grande & Nicki Minaj - "Bang Bang"
John Legend - "All Of Me"
John Mayer - "Who Says"
JoJo - "Too Little Too Late"
Jonas Brothers - "A Little Bit Longer"
Jonas Brothers - "Burnin' Up"
Jonas Brothers - "Pushin' Me Away"
Jonas Brothers - "S.O.S."
Jonas Brothers - "Tonight"
Jordan Smith - "Great Is Thy Faithfulness (The Voice Performance)"
Jordan Smith - "Mary, Did You Know (The Voice Performance)"
Jordan Smith - "Somebody to Love (The Voice Performance)"
Justin Bieber - "All Bad"
Justin Bieber - "All That Matters"
Justin Bieber - "Boyfriend"
Justin Bieber - "Change Me"
Justin Bieber - "Confident (feat. Chance The Rapper)"
Justin Bieber - "Die In Your Arms"
Justin Bieber - "Heartbreaker"
Justin Bieber - "Love Yourself"
Justin Bieber - "Mistletoe"
Justin Bieber - "Pyd (feat. R. Kelly)"
Justin Bieber - "Roller Coaster"
Justin Bieber - "What Do You Mean?"
Justin Timberlake - "CAN'T STOP THE FEELING! (Original Song From DreamWorks Animation's "Trolls")"
Justin Timberlake - "Hallelujah (feat. Matt Morris & Charlie Sexton)"
Justin Timberlake - "My Love (feat. T.I.)"
Justin Timberlake - "SexyBack"
Justin Timberlake - "Suit & Tie (feat. Jay-Z)"
Justin Timberlake - "What Goes Around... Comes Around"

Kanye West - "All Day (feat. Theophilus London, Allan Kingdom & Paul McCartney)"
Kanye West - "Gold Digger (feat. Jamie Foxx)"
Kanye West - "Heartless"
Kanye West - "Love Lockdown"
Kanye West - "Stronger"
Kanye West, Jay-Z & Big Sean - "Clique"
Katy Perry - "California Gurls (feat. Snoop Dogg)"
Katy Perry - "Dark Horse (feat. Juicy J)"
Katy Perry - "E.T. (feat. Kanye West)"
Katy Perry - "Firework"
Katy Perry - "I Kissed A Girl"
Katy Perry - "Last Friday Night (T.G.I.F.)"
Katy Perry - "Part Of Me"
Katy Perry - "Rise"
Katy Perry - "Roar"
Katy Perry - "Teenage Dream"
Katy Perry - "Wide Awake"
Ke$ha - "Blah Blah Blah (feat. 3OH!3)"
Ke$ha - "Tik Tok"
Ke$ha - "We R Who We R"
Kelly Clarkson - "Breakaway"
Kelly Clarkson - "My Life Would Suck Without You"
Kelly Clarkson - "Piece By Piece"
Kelly Clarkson - "Piece By Piece (Idol Version)"
Kelly Clarkson - "What Doesn't Kill You (Stronger)"
Kenny Chesney - "Setting the World On Fire (with P!nk)"
Kris Allen - "No Boundaries"
Lady Antebellum - "Need You Now"
Lady Gaga - "Bad Romance"
Lady Gaga - "Born This Way"
Lady Gaga - "Judas"
Lady Gaga - "Just Dance (feat. Colby O'Donis & Akon)"
Lady Gaga - "Million Reasons"
Lady Gaga - "Perfect Illusion"
Lady Gaga - "Poker Face"
Lady Gaga - "The Edge Of Glory"
Lana Del Rey - "High By The Beach"
Leona Lewis - "Bleeding Love"
Lil Wayne - "6 Foot 7 Foot (feat. Cory Gunz)"
Lil Wayne - "Lollipop (feat. Static Major)"
Lil Wayne - "Right Above It (feat. Drake)"
Lil Wayne - "She Will (feat. Drake)"
Linkin Park - "New Divide"
Little Big Town - "Better Man"
LL Cool J - "Control Myself (feat. Jennifer Lopez)"
LMFAO - "Party Rock Anthem (feat. Lauren Bennett & GoonRock)"
LMFAO - "Sexy And I Know It"
Lorde - "Royals"
Ludacris - "Money Maker (feat. Pharrell)"
Lukas Graham - "7 Years"
Machine Gun Kelly & Camila Cabello - "Bad Things"
Macklemore & Ryan Lewis - "Can't Hold Us (feat. Ray Dalton)"
Macklemore & Ryan Lewis - "Thrift Shop (feat. Wanz)"
Madonna - "4 Minutes (feat. Justin Timberlake & Timbaland)"
Madonna - "Hung Up"
MAGIC! - "Rude"
Major Lazer - "Cold Water (feat. Justin Bieber & MØ)"
Mariah Carey - "All I Want For Christmas Is You"
Mariah Carey - "Don't Forget About Us"
Mariah Carey - "Touch My Body"
Mark Ronson - "Uptown Funk (feat. Bruno Mars)"
Maroon 5 - "Don't Wanna Know (feat. Kendrick Lamar)"
Maroon 5 - "Makes Me Wonder"
Maroon 5 - "Moves Like Jagger (feat. Christina Aguilera)"
Maroon 5 - "Payphone (feat. Wiz Khalifa)"
Maroon 5 - "She Will Be Loved"
Maroon 5 - "This Love"
Matt McAndrew - "Wasted Love (The Voice Performance)"
Matthew Schuler - "Hallelujah (The Voice Performance)"
Meghan Trainor - "All About That Bass"
Meghan Trainor - "NO"
Michael Jackson - "Man In The Mirror"
Miley Cyrus - "Can't Be Tamed"
Miley Cyrus - "Party In The U.S.A."
Miley Cyrus - "We Can't Stop"
Miley Cyrus - Wrecking Ball"
MIMS - "This Is Why I'm Hot"
Miranda Lambert - "Vice"
Mumford & Sons - "Believe"
Ne-Yo - "So Sick"
Nelly Furtado - "Promiscuous (feat. Timbaland)"
Nelly Furtado - "Say It Right"
Niall Horan - "This Town"
Nickelback - "Photograph"
Nicki Minaj - "Anaconda"
Norah Jones - "Sunrise"
Omi - "Cheerleader (Felix Jaehn Remix Radio Edit)"
One Direction - "Best Song Ever"
One Direction - "Drag Me Down"
One Direction - "Home"
One Direction - "Infinity"
One Direction - "Live While We're Young"
One Direction - "One Way Or Another (Teenage Kicks)"
One Direction - "Perfect"
One Direction - "Steal My Girl"
One Direction - "Story Of My Life"
OutKast - "Hey Ya!"
Owl City - "Fireflies"
P!nk - "F**kin' Perfect (Perfect)"
P!nk - "Just Give Me A Reason (feat. Nate Ruess)"
P!nk - "So What"
Panic! At the Disco - "Victorious"
Paris Hilton - "Stars Are Blind"
Pharrell Williams - "Happy (from "Despicable Me 2")"
Phillip Phillips - "Home"
Phillip Phillips - "Home (American Idol Performance)"
Pitbull - "Timber (feat. Ke$ha)"
Plain White T's - "Hey There Delilah"
Prince & The Revolution - "Purple Rain"
PSY - Gangnam Style (강남스타일)"
Rachel Platten - "Fight Song"
Rae Sremmurd - "Black Beatles (feat. Gucci Mane)"
Rihanna - "Bitch Better Have My Money"
Rihanna - "Diamonds"
Rihanna - "Disturbia"
Rihanna - "Only Girl (In The World)"
Rihanna - "Pon De Replay"
Rihanna - "Russian Roulette"
Rihanna - "S&M (Remix) [feat. Britney Spears]"
Rihanna - "SOS"
Rihanna - "Stay (feat. Mikky Ekko)"
Rihanna - "Take A Bow"
Rihanna - "Umbrella (feat. Jay-Z)"
Rihanna - "We Found Love (feat. Calvin Harris)"
Rihanna - "What's My Name? (feat. Drake)"
Rihanna - "Work (feat. Drake)"
Rihanna and Kanye West and Paul McCartney - "FourFiveSeconds"
Robin Thicke - "Blurred Lines (feat. T.I. & Pharrell)"
Sam Smith - "I'm Not The Only One"
Sam Smith - "Writing's On the Wall"
Sara Bareilles - "Love Song"
Scotty McCreery - "I Love You This Big (American Idol Performance)"
Sean Kingston - "Beautiful Girls"
Selena Gomez - "Good For You (feat. A$AP Rocky)"
Shakira - "Hips Don't Lie (feat. Wyclef Jean)"
Shawn Mendes - "Life of the Party"
Shawn Mendes - "Treat You Better"
Sia - "Cheap Thrills (feat. Sean Paul)"
Snoop Dogg - "Drop It Like It's Hot"
Snoop Dogg & Wiz Khalifa - "Young, Wild & Free (feat. Bruno Mars)"
Snow Patrol - "Chasing Cars"
Soulja Boy Tell 'Em - "Crank That (Soulja Boy)"
Sundance Head - "Me and Jesus (The Voice Performance)"
T.I. - "Live Your Life (feat. Rihanna)"
T.I. - "Whatever You Like"
Taio Cruz - "Break Your Heart (feat. Ludacris)"
Taio Cruz - "Dynamite"
Tamar Braxton - "Love And War"
Taylor Swift - "Back To December"
Taylor Swift - "Bad Blood (feat. Kendrick Lamar)"
Taylor Swift - "Begin Again"
Taylor Swift - "Blank Space"
Taylor Swift - "Change"
Taylor Swift - "Everything Has Changed (feat. Ed Sheeran)"
Taylor Swift - "Fearless"
Taylor Swift - "I Knew You Were Trouble."
Taylor Swift - "If This Was A Movie"
Taylor Swift - "Jump Then Fall"
Taylor Swift - "Mean"
Taylor Swift - "Mine"
Taylor Swift - "Out Of The Woods"
Taylor Swift - "Red"
Taylor Swift - "Ronan"
Taylor Swift - "Safe & Sound (From "The Hunger Games" Soundtrack) [feat. The Civil Wars]"
Taylor Swift - "Shake It Off"
Taylor Swift - "Sparks Fly"
Taylor Swift - "Speak Now"
Taylor Swift - "State Of Grace"
Taylor Swift - "Today Was A Fairytale"
Taylor Swift - "We Are Never Ever Getting Back Together"
Taylor Swift - "White Horse"
Taylor Swift - "You Belong With Me"
Taylor Swift - "You're Not Sorry"
Tessanne Chin - "Bridge Over Troubled Water (The Voice Performance)"
Tessanne Chin - "I Have Nothing (The Voice Performance)"
The All-American Rejects - "Dirty Little Secret"
The Black Eyed Peas - "Boom Boom Pow"
The Black Eyed Peas - "Don't Phunk With My Heart"
The Black Eyed Peas - "I Gotta Feeling"
The Black Eyed Peas - "Imma Be"
The Black Eyed Peas - "Just Can't Get Enough"
The Black Eyed Peas - "Let's Get It Started (Spike Mix)"
The Black Eyed Peas - "My Humps"
The Black Eyed Peas - "The Time (Dirty Bit)"
The Chainsmokers - "Closer (feat. Halsey)"
The Click Five - "Just The Girl"
The Fray - "How To Save A Life"
The Lumineers - "Ho Hey"
The Weeknd - "Can't Feel My Face"
The Weeknd - "Starboy (feat. Daft Punk)"
Timbaland - "Apologize (feat. OneRepublic)"
Timbaland - "Give It To Me (feat. Nelly Furtado & Justin Timberlake)"
Train - "Hey, Soul Sister"
twenty one pilots - "Heathens"
twenty one pilots - "Stressed Out"
U2 - "Vertigo"
Usher - "Love In This Club (feat. Young Jeezy"
Usher - "OMG (feat. will.i.am)"
Usher - "Yeah! (feat. Lil Jon & Ludacris)"
Usher & Alicia Keys - "My Boo"
Weezer - "Beverly Hills"
"Weird Al" Yankovic - "White & Nerdy (Parody Of Ridin' Dirty)"
Whitney Houston - "I Will Always Love You"
Will Smith - "Switch"
will.i.am - "Scream & Shout (feat. Britney Spears)"
Wiz Khalifa - "Black & Yellow"
Wiz Khalifa - "No Sleep"
Wiz Khalifa - "See You Again (feat. Charlie Puth)"
Zach Sobiech - "Clouds"
ZAYN - "PILLOWTALK"
ZAYN & Taylor Swift - "I Don't Wanna Live Forever (Fifty Shades Darker)"

Lil Wayne feat. Drake - Right Above it

Miley Cyrus - Party In The USA

Drake feat. Rihanna- Take Care

Kind of random, but I remember I Do by Colbie Caillat hitting #1 for a couple hours in the morning before Born This Way got there.

fun fact: Beyonce's "Crazy In Love" was the 1st #1 on iTunes

Ashlee Simpson - Invisible

I remember that it reached the #1 spot for a short time

Drake f/ Nicki Minaj - Make Me Proud

Please no lies!

Did 'Bleeding Love' go #1?

Rihanna-Only Girl (In The World)

Only Girl by Rihanna also.

Taylor Swift - Speak Now
Taylor Swift - Sparks Fly

I'm not quite so sure about her Fearless era...

Katy Perry - I Kissed a Girl
Fergie - London Bridge
Paris Hilton - Stars are Blind
Alicia Keys - No One

Sure. It's biggest US hit.

Rihanna- Umbrella

Really?

Make that history Bey!!! As if it only sold 500k....if it was out now...sweet lord....7m US sales anyone? (taking that from RITD's run at the top for 7 weeks too) And DIL would have been at 6m US