“I agree 100 percent with the courts,” he said on "Fox and Friends" this morning. “In that case, we should open it up.”
Apple received a court order on Tuesday to assist the FBI in breaking encryption codes on the iPhone belonging to Syed Rizwan Farook, one of the attackers in the San Bernardino attack in California.
“To think that Apple won't allow us to get into her cell phone -- who do they think they are?” Trump said. “No, we have to open it up.”
The FBI said that only Apple can help hack into the iPhone. "Apple has the exclusive technical means which would assist the government in completing its search, but has declined to provide that assistance voluntarily," investigators said.
But Apple argues that providing access to this cell phone would make it possible to hack into any other iPhone as well.
"The implications of the government’s demands are chilling," Apple CEO Tim Cook said in a statement. "The government suggests this tool could only be used once, on one phone. But that’s simply not true. Once created, the technique could be used over and over again, on any number of devices. In the physical world, it would be the equivalent of a master key, capable of opening hundreds of millions of locks -- from restaurants and banks to stores and homes."
“This is one case, and this is a case that certainly we should be able to get into the phone,” Trump said.
But he's not the only presidential candidate commenting on the situation. His GOP rivals, Florida Sen. Marco Rubio and Ohio Gov. John Kasich, are also siding with the court, though with different tones.
Rubio said he hopes Apple will cooperate “voluntarily,” and emphasized the need to work with tech companies to find a solution.
Kasich said he did not think it was government over-reach to hack into the phone, and that Apple and the U.S. government shouldn’t be fighting because it’s the “the last thing we need.”
Kasich was also reluctant to talk about this issue, saying it shouldn’t be discussed in public.
ABC News' Alana Abramson contributed to this report.