“Now he has to try to return to his every day life,” said defence lawyer Kerstin Koorti, to newspaper Metro.
The teenager was previously known to the police, and when remanded into custody was facing charges of attempted murder or alternatively aggravated assault.
According to police they no longer suspect him for planning the incident.
However, he is still under suspicion for aggravated assault or the alternative charge of complicity to aggravated assault.
The boy was brought in for questioning a few days after an explosion at a pre-school in the Stockholm district of Sköndal seriously injured a four-year-old girl.
After that, two more explosive devices were found in the area.
Police detonated a homemade charge after it had been discovered hanging from a goal on a football field a few days after the pre-school blast.
A day or so later, a third device was found near a playground, only metres away from playing children.
An 18 –year-old was also brought in for questioning and was subsequently remanded into custody.
Questioning other people has led police to conclude that the 15-year-old was less involved in the incidents than previously believed.
“We have questioned several people. Often this leads to suspicions increasing but not in this case,” said prosecutor Åsa Andersson.
According to Koorti, the boy has had a hard time being locked up while in custody and has received extra support.