Raised in Spain from the age of 12, Andone began competing in the country's lower divisions before making his professional debut for La Liga team Córdoba in 2014.

Andone earned his first full cap for Romania in a goalless draw with Northern Ireland in June 2015, and was selected in the squad for the UEFA Euro 2016.

Born in Botoșani, Andone moved to Vinaròs in the Valencian Community in 2005, aged 12, to join his mother after his father died in a car accident.

[3] Andone made his senior debut on 16 January 2011, coming on as a late substitute for Pau Franch in a 1–1 away draw against Orihuela in the Segunda División B championship.

[8] Andone played his first match as a professional on 3 December 2014, replacing Xisco in the 57th minute of a 1–0 away loss against Granada, for the season's Copa del Rey.

[21] He ended his season with 21 goals after scoring the game's only at Mallorca to achieve a play-off place on 29 May, missing the final round in order to join up with Romania;[22] he was ultimately beaten to the division's Pichichi Trophy by Elche's Sergio León.

[24][25] He was given the number 10 jersey and made his debut as a substitute on 19 August in a 2–1 home win against Eibar,[26] scoring his first goal on 5 November to open a 1–1 draw at Granada.

[35] On 25 May 2018, Andone signed a five-year deal with Brighton & Hove Albion for an undisclosed fee, and joined the Premier League side when the international transfer window opened on 8 June.

[42][43] After three league appearances, one goal and a red card for Brighton in August 2019, Andone agreed to a season-long loan with Turkish Süper Lig side Galatasaray on 2 September.

[51] On 1 September 2022, Andone signed a one-season deal with Segunda División side UD Las Palmas on the final day of the summer transfer window.

[58] On 17 November 2015, Andone scored his first international goal, exploiting an error by Italian goalkeeper Salvatore Sirigu for a last-minute equaliser in a 2–2 draw in Bologna.

[59] He was selected for UEFA Euro 2016 in France, where he started against the hosts in the opening game after recovering from a hand injury,[60] and made two more substitute appearances in a group-stage exit.