Gaga began work on her third studio album, Artpop, in early 2012, during the Born This Way Ball tour; she crafted the album to mirror "a night at the club". In August 2013, Gaga released the album's lead single "Applause", which reached number one in Hungary, number four in the US, and number five in the UK. A lyric video for Artpop track "Aura" followed in October to accompany Robert Rodriguez's Machete Kills, where she plays an assassin named La Chameleon. The film received generally negative reviews and earned less than half of its $33 million budget. The second Artpop single, "Do What U Want", featured singer R. Kelly and was released later that month, topping the charts in Hungary and reaching number 13 in the US. Gaga removed the song from all streaming platforms in 2019 in the light of allegations made against Kelly sexually abusing several women; Gaga apologized for ever collaborating with him. Artpop was released on November 6, 2013 to mixed reviews. Helen Brown in The Daily Telegraph criticized Gaga for making another album about her fame and doubted the record's originality, but found it "great for dancing". The album debuted atop the Billboard 200 chart, and sold more than 2.5 million copies worldwide as of July 2014. "G.U.Y." was released as the third single in March 2014 and peaked at number 76 in the US.
Time placed Gaga on their All-Time 100 Fashion Icons List, stating: "Lady Gaga is just as notorious for her outrageous style as she is for her pop hits ... [Gaga] has sported outfits made from plastic bubbles, Kermit the Frog dolls, and raw meat." Gaga wore a dress made of raw beef to the 2010 MTV Video Music Awards, which was supplemented by boots, a purse, and a hat also made out of raw beef. Partly awarded in recognition of the dress, Vogue named her one of the Best Dressed people of 2010 and Time named the dress the Fashion Statement of the year. It attracted the attention of worldwide media; the animal rights organization PETA found it offensive. The meat dress was displayed at the National Museum of Women in the Arts in 2012, and entered the Rock and Roll Hall of Fame in September 2015.
Gaga's fans call her "Mother Monster", and she often refers to them as "Little Monsters", a phrase which she had tattooed on herself in dedication. In his article "Lady Gaga Pioneered Online Fandom Culture As We Know It" for Vice, Jake Hall wrote that Gaga inspired several subsequent fan-brandings, such as those of Taylor Swift, Rihanna and Justin Bieber. In July 2012, Gaga also co-founded the social networking service LittleMonsters.com, devoted to her fans. According to Guinness World Records, Gaga was the most followed person on Twitter in 2011, and the most followed female pop singer and the most powerful popstar in 2014. Forbes included Gaga on its Celebrity 100 from 2010 to 2015 and then from 2018 to 2020 and its list of the World's Most Powerful Women from 2010 to 2014. She earned $62 million, $90 million, $52 million, $80 million, $33 million, and $59 million from 2010 through 2015, and $50 million, $39 million and $38 million between 2018 and 2020. She was named one of the most influential people in the world by Time magazine in 2010 and 2019, and ranked second in most influential people of the past ten years in a Time magazine readers' poll in 2013. In March 2012, Gaga was ranked fourth on Billboard's list of top moneymakers of 2011 with earnings of $25 million, which included sales from Born This Way and her Monster Ball Tour. The following year, she topped Forbes' List of Top-Earning Celebs Under 30, and in February 2016, the magazine estimated Gaga's net worth to be $275 million. In December 2019, Gaga placed 10th on Forbes' list of Top-Earning Musicians Of The Decade with earnings of $500 million in the 2010s; she was the fourth highest-earning female musician on the list.
In 2012, Gaga joined the campaign group Artists Against Fracking. That October, Yoko Ono gave Gaga and four other activists the LennonOno Grant for Peace in Reykjavík, Iceland. The following month, Gaga pledged to donate $1 million to the American Red Cross to help the victims of Hurricane Sandy. Gaga also contributes in the fight against HIV and AIDS, focusing on educating young women about the risks of the disease. In collaboration with Cyndi Lauper, Gaga joined forces with MAC Cosmetics to launch a line of lipstick under their supplementary cosmetic line, Viva Glam. Sales have raised more than $202 million to fight HIV and AIDS.
In 2012, Gaga launched the Born This Way Foundation (BTWF), a non-profit organization that focuses on youth empowerment. It takes its name from her 2011 single and album. Media proprietor Oprah Winfrey, writer Deepak Chopra, and US Secretary of Health and Human Services Kathleen Sebelius spoke at the foundation's inauguration at Harvard University. The foundation's original funding included $1.2 million from Gaga, $500,000 from the MacArthur Foundation, and $850,000 from Barneys New York. In July 2012, the BTWF partnered with Office Depot, which donated 25% of the sales, a minimum of $1 million of a series of limited edition back-to-school products. The foundation's initiatives have included the "Born Brave Bus" that followed her on tour as a youth drop-in center as an initiative against bullying.