[11][12][13][14] Heartbreaker was created during a three-week period in November 2020 at a rented Bucharest mansion with two recording studios, in which Inna resided with Romanian songwriters and producers Sebastian Barac, Marcel Botezan, Ciente, Alexandru Cotoi and Minelli.

[29] Bradley Stern of MuuMuse called Inna a "solid supplier" and "damn prolific", praising her decision to issue a completely new body of work with Heartbreaker and not stretch it out by not adding the previously released non-album singles to its tracklist.

The album opens with the Arabic music and reggaeton-inspired "Maza Jaja"[30] and "One Reason", with Stern commenting that the latter is "bound to be on heavy rotation at my Russian barbershop in Midtown that solely blasts deep house dance hits".

The Spanish-language "label brag" "Gucci Balenciaga" includes the explicit lyrics "me importa una mierda" (Spanish: "I don't give a shit"),[31] and is followed by the title "Heartbreaker", which InfoMusic's Alex Stănescu picked as the album's highlight, noticing its oriental influences as well as the use of a synthesizer and vocal chopping.

[26] While Stern likened "Sunset Dinner" to American recording artist Britney Spears' "Change Your Mind (No Seas Cortes)" off her 2016 studio album Glory, he praised "Thicky" as "stand[ing] out above the rest".

[33] Upon entering the Shazam chart in Russia,[34] "Flashbacks" experienced commercial success on the radio ranking in the region, as well as in those of Romania, Bulgaria, Ukraine and the Commonwealth of Independent States, peaking at numbers one, four, seven, nine and two, respectively.

[44][45] All tracks lyrics written by Elena Alexandra Apostoleanu (Inna) and Luisa Luca whereas musical composition was done by producers Alexandru Cotoi, Sebastian Barac, Marcel Botezan and David Ciente.