How this technology may have helped FBI access locked phone of Trump's shooter in two days

Two days after the assassination attempt on former US President Donald Trump, the Federal Bureau of Investigation (FBI) announced that they had “gained access” to the shooter's phone. The agency did not reveal how they managed to break into the device or what information they discovered. However, the rapid success suggests the use of advanced phone-hacking tools.
“FBI technical specialists successfully gained access to Thomas Matthew Crooks’ phone, and they continue to analyse his electronic devices,” the FBI said, without mentioning the name and model of the phone. The agency, however, failed in its first attempt to break into the shooter’s phone.
According to a report by The Verge, when field agents in Pennsylvania failed to ‘crack’ the phone, the FBI sent it to its lab in Quantico, Virginia where they took the help of security researchers to break into the phone.

The publication cited Cooper Quintin, a security researcher and senior staff technologist with the Electronic Frontier Foundation, saying that the law enforcement agencies possess tools to extract data from phones.
“Almost every police department in the nation has a device called the Cellebrite, which is a device built for extracting data from phones, and it also has some capability to unlock phones,” Quintin was quoted as saying.
Cellebrite, an Israel-based company, provides mobile device extraction tools (MDTFs) to law enforcement. The report noted that these tools come from various vendors and offer different capabilities for extracting data from mobile devices. Their efficacy – how well they work – can vary significantly. It's likely the FBI has its own internal forensics tools developed specifically for their needs.
“It seems reasonable to me that the field office there [in Pennsylvania] wouldn’t have some of the more advanced techniques for breaking into modern phones that they have at Quantico,” Quintin said, adding that he had “little doubt that Quantico will be able to break into this phone”.

In a previous case, the FBI had demanded that Apple unlock an iPhone of the shooter in the San Bernardino shooting case in 2016. However, the company refused, saying that it cannot create a backdoor.
“The FBI may use different words to describe this tool, but make no mistake: Building a version of iOS that bypasses security in this way would undeniably create a backdoor. While we believe the FBI’s intentions are good, it would be wrong for the government to force us to build a backdoor into our products. And ultimately, we fear that this demand would undermine the very freedoms and liberty our government is meant to protect,” Apple CEO Tim Cook said at that time.
The FBI later dropped the case because it got help from an “outside source” to break into the device.