In the United States, "Lips Are Movin" reached number 4 on the Billboard Hot 100 and was certified quadruple platinum by the Recording Industry Association of America (RIAA).

[1] They subsequently co-wrote the song "All About That Bass" in November 2013 and pitched it to different record labels, all of which turned it down due to its doo-wop pop production as synth-pop was more popular at the time.

[10] Trainor told The Tennessean that the musical composition of "Lips Are Movin" and "All About That Bass" follows the same formula, which Slant Magazine's Alexa Camp described as "doo-wop throwback, girl-group harmonies, bubblegum pop hooks".

[7] However, reviewers, including The Tennessean's Dave Paulson and MTV News' Christina Garibaldi, deemed it a track about leaving a significant other after being cheated on, an interpretation Kadish is open to.

"[7] On October 14, 2014, "Lips Are Movin" was briefly available to stream on mobile application Shazam, and premiered along with its artwork on MTV News the following day.

[12] Sony Music released a CD single exclusively for sale by United States retailer Best Buy on December 30, 2014, and in Germany on February 13, 2015.

[32] Writing for Clash, Alice Levine remarked that the songs have the same "factory-produced sass" and theme of false feminism and empowerment, but being done a second time decreased its novelty.

[33] The Boston Globe's Marc Hirsh derided "Lips Are Movin" for following the formula of "All About That Bass", writing that Trainor is a plunderer and "steals from herself" with the song.

[35] Toronto Star's Ben Rayner wrote that it is "whitewashed into a fairly anodyne mush", and declared that its "hip-hop bump and plush bassline" are "pure cosmetic window dressing".

Billboard's Carl Wilson complimented the lyrics, saying that they proved Trainor had "more going on than a topical trifle", but concluded that the song was risking "coming off as 'Bass, Part 2".

[38] Garibaldi described it as an up-beat and catchy "ladies anthem",[19] and a Billboard critic stated that the "upbeat and sassy" song's similarities with "All About That Bass" would lead to "great things" for it.

This made Trainor the fifth female artist in Billboard Hot 100 chart history to follow her debut number-one single directly with a second top-five.

[41][8] The Recording Industry Association of America (RIAA) certified the single 4× Platinum, which denotes four million units based on sales and track-equivalent on-demand streams.

[19][79] Hewlett-Packard and ad agency 180LA had been contacting record labels, wanting to help create a music video as part of the promotional campaign for the former's newly launched Pavilion x360 laptop, when they thought of Trainor.

A creative director for 180LA told Adweek that they picked Trainor as her music would suit a "fun, high-energy campaign" and she had the potential to inspire the influencers' followers.

[80] Trainor described the concept of the video in an interview with MTV News: "Here's me being sassy and other people dancing with me and having just a good time and trying to get through this feeling of, Ugh he's cheating on me again".

[82] Lips are used as a motif throughout the video; they appear as close-ups of Trainor's mouth, lip-shaped earrings and sunglasses, and as a large drawing in the backdrop, the latter of which Yahoo!

[83] The music video's release reportedly boosted Trainor's social media presence, including an 11% surge in Twitter followers, 16% on Facebook, 41.3% on Instagram, and an almost 100% increase on Vine.

[77][79] Hampp said that in being the first-ever music video created entirely by social media influencers, its production was a "historic milestone in the realm of YouTube creators".

[79] James Cowan of Canadian Business believed that some could see Hewlett-Packard's involvement as a dull brand trying to appear modish by attaching itself to influencers, but a more enthusiastic viewer may call it "arts patronage for the 21st century", and noted that the sponsorship is so limited that no one would notice it without searching.

[83] Fuse's Hilary Hughes wrote that the "Lips Are Movin" music video offered a bolder look for Trainor, which constituted a style shift from the latter and "definitely made a statement", but retained its "cheekiness and big-eyed adorable vibes".