[2] As a pop song, "Write on Me" was noted for having "slow melody" in comparison to Fifth Harmony's previous works, using synths, tambourines, finger-snaps and an acoustic guitar as its foundation.
[5][4][3][6] As for Sasha Geffen from MTV News, the song blends "acoustic guitar chords with tropical synths", while using a calm instrumentation instead of "big beats".
[7] Cabello said that it was her personal favorite song, saying that the track was "an extended metaphor where you're asking somebody to 'write' on you, envelop you with their words, make their mark on you like you're a blank canvas.
[9] Billboard magazine expressed similar statements to Getz, calling the song powerful while also distinguishing the "laid back" atmosphere from their past single, "Work from Home".
"[10] Some writers such as Brittany Spanos from Rolling Stone, Fuse's Jeff Benjamin and Brennan Carley of Spin acclaimed the song noting its resemblance to Kygo's musical style.
"[5] The video begins with a guitar being strummed in a cartoonish background as each member's white silhouette is shown making dramatic motions.
The scene transitions as multiple thick grey and black rectangular lines move towards the chorus of the song where each member is singing in stools, snapping their fingers with a spotlight on them.
In a negative special effects, the verse changes to Cabello, who is presented in different takes, including a silhouette, a normal background and a dim mirror image.
As the video progresses, the rhythm intensifies with several individual takes of the group as the grey rectangular boxes slow the beat with a moving background of a sunset and blurry blue lines depicting waves as Cabello's image disappears.
The video ends with each member's silhouette making hand motions as the camera pans upwards to reveal the album's title and group's logo.