Krkic has been without a club since leaving Japanese side Vissel Kobe in January.
He burst onto the scene as a talented 17-year-old in 2007 and went on to make 163 appearances in total for Barcelona scoring, 41 goals.
Bojan won three La Liga titles and two UEFA Champions League trophies with Barcelona but ultimately failed to live up to the hype of his younger days.
After spending time in Italy with AS Roma and AC Milan, Bojan joined Stoke City in 2014, where he spent five years before a nomadic end to his career saw him play for Mainz 05, Alaves and Montreal Impact.
Bojan played under some of the best managers in world football, including Pep Guardiola and Massimiliano Allegri, but picked out Frank Rijkaard for special praise in his farewell press conference at the Camp Nou.
"These decisions are not easy. I have been away from home for 12 years and I feel fulfilled professionally," he said.
"I wanted to enjoy the next stage [of my life] closer to my family. It's not a physical issue.
"I have had three injuries, but I recovered, I am 100%. It is a feeling, it's the reality. I am more excited about doing other things now than to keep playing football. I am grateful for everything I have experienced.
"I have played for Barcelona, I've played with great players, I have won trophies and I have played in other leagues. But I am ready to start new things now."
"All the coaches make a mark on you. But the most, Frank Rijkaard," Bojan added.
"He gave me the opportunity and continuity to back myself. Without him, my career would not have been possible."
Bojan won one cap for Spain in 2008.
