Aruán's solo piano performance, "Heritage," translates folkloric rhythmic patterns from the Franco-Haitian realm from the southeastern part of Cuba, such as Tumba Francesa, Gagá, and Tahona into a series of musical pieces stylistically distant, such as avant-garde jazz and contemporary music, using improvisation as a common source of self-expression. 

Between 2003 and 2015, he led or co-led excellent hardcore jazz albums such as Alameda, Orbiting and Banned In London, and spent several years playing piano and keyboards with Wallace Roney, with whom he recorded twice. Before arriving in New York in 2008, Aruán played with Esperanza Spalding on her debut album, "Junjo" (Ayva Música, 2006), and was described by DownBeat Magazine as "...one of the most versatile and exciting pianists of his generation..."

In 2012 he composed and conducted Santiarican Blues Suite—a five-part score that references a wide timeline of Cuban, Afro-Haitian and contemporary classical vocabulary—with a camerata of string quartet, two basses, two pianos, flute and percussion. The album received 4.5 stars from DownBeat, and Latin Jazz Network said, “This record by a very special artist will go down as one of the most significant works of music." 

In 2013 he produced and curated several series of concerts featuring some of the most legendary, forward-thinking, and creative improvisers on the New York scene such as Andrew Cyrille, Oliver Lake, Henry Grimes, Sam Newsome, Rufus Reid, Francisco Mora-Catlett, Ralph Alessi and Don Byron. The performances explored the translation of non-musical patterns, symbols, and structures into concepts unusual to jazz improvisation and notated music. Of the Music & Architecture Concert Series (2013) Tomas Pena of the Latin Jazz Network stated, "...The music evoked images of mathematical equations, great architectural works and brought to mind the New York loft scene of the 1970s, where free jazz reigned supreme." 

In 2016 Aruán released his critically acclaimed CD Hidden Voices (Intakt Records), featuring Eric Revis on bass and Gerald Cleaver on drums. The recording advances Aruán’s groundbreaking work into new territory, where his Afro-Cuban and hardcore jazz roots are implied but not explicitly stated. “I have been writing tunes flirting with atonal and serial music for quite a while, finding harmonic movements that might not be familiar to some ears, and adding some Cuban Cubism to the palette,” he says. The album has earned broad critical acclaim including 5 stars from Jazzism Magazine, and 4 stars from The Irish Times, DownBeat and All About Jazz. 

"Aruán Ortiz weaves multiple strands of tradition through his music, with an endgame of deep mystification. A pianist originally from Cuba, he has been a creative force at least since the release of his debut album 20 years ago. But he’s moving into a new tier with Hidden Voices.” Nate Chinen, New York Times 

 “A solid and unique new sound in today’s jazz world.”  Matthew Fiander, PopMatters 

He has received accolades including the Doris Duke Impact Award (2014); Composers Now Creative Residency Award at Pocantico Center of the Rockefeller Brothers Fund (2014); the Jerome Foundation Travel & Study Grant (2013); Latin Jazz Corner’s Arranger of the Year (2011) for his contribution on the album El Cumbanchero by flutist Mark Weinstein (Jazzheads, 2011); Fundación Autor, SGAE, and Generalitat de Catalunya Grant study grants (2002); Semifinalist, Jas Hennessy Piano Solo Competition, Montreux, Switzerland (2001); and Best Jazz Interpretation, Festival de Jazz in Vic, Spain (2000).

In addition to touring in Europe and the US with his own trio and quartet, Aruán has also played, toured, or recorded with artists including Esperanza Spalding, Terri Lyne Carrington, Wadada Leo Smith, Don Byron, Greg Osby, Wallace Roney, Nicole Mitchell, Steve Turre, Cameron Brown, and Nasheet Waits.