[6] They are best known for their 2013 single "Cool Kids", which peaked at number 13 on the Billboard Hot 100 and received quadruple platinum certification by the Recording Industry Association of America (RIAA).

The band has mentioned that numerous rock artists, including Coldplay, Echo & the Bunnymen, the Smiths, the Killers, U2, Joy Division, and Fleetwood Mac influenced them while growing up and encouraged them to make music together.

[11] Echosmith has also released an array of covers of songs such as "I Will Wait" by Mumford & Sons,[12] "Lights" by Ellie Goulding,[13] "Set Fire to the Rain" by Adele,[14] and "Princess of China" by Coldplay and Rihanna.

[18] Echosmith launched a Summer Sampler free download promo on their website, with the songs "Cool Kids", "Come Together", and "Talking Dreams".

[19] On June 7, 2013, the band performed a free concert at Warner Bros. Records in Burbank, CA, with simultaneous streaming through Echosmith's YouTube channel.

[31] Leading up to the release, the acoustic version of "Cool Kids" was premiered on the group's YouTube channel on June 3.

[35] In 2015, Echosmith provided the vocals for Russian-German DJ and musician Zedd's track "Illusion", featured on his second studio album titled True Colors.

[41] One week later, the band performed their new single live for the first time at the 2017 MTV Fandom Awards during San Diego Comic-Con.

After a prior announcement delaying the album and tour until Spring 2018, the Inside a Dream EP was released in its stead on September 29, 2017.

[48][49] In March 2018, the band released a new lead single, "Over My Head,"[50] pushing the album to summer,[51][52] and subsequently delaying it indefinitely.

[53] Later that summer, the band opened for Pentatonix on their tour[54] and rounded out the year with a Christmas show in San Diego on December 8, 2018.

[55] On March 8, 2019, Echosmith released their single "Favorite Sound," as a collaboration with musician Audien,[56][57] as well as a cover of "Reflektor" by Arcade Fire,[58] originally from 2013.