The novel is told from four points of view: Virgil Salinas, a Filipino-American boy; Kaori Tanaka, a Japanese-American girl; Valencia Somerset, a girl in Virgil's class who is deaf; and Chet Bullens, the neighborhood bully.

In a more mixed review, Sarah Hannah Gomez writing for the Horn Book Magazine stated, "while the ending may be a bit too tidy, the children’s inner lives are distinctive, and each rings true.

"[5] The diversity presented by the characters and the low-key way this was handled was also praised in several reviews, including by Angie Bayne writing for the Jefferson City News Tribune, "diversity is not treated as a plot point but just a point of fact.

The selection committee noted that the book was "masterfully told through shifting points of view," adding that "this modern quest tale shimmers with humor and authentic emotion.

[2] The German edition of Hello, Universe was awarded the 2019 Deutscher Jugendliteraturpreis, the country's highest honor for children's literature.