The FBI has promised to leave no stone unturned during their investigation. Farook has a locked Iphone that is encrypted by default.
As we already know from past criminal cases, the FBI has sought and has gotten Apple’s help to retrieve data from phones.
In many cases no help was needed as there where a wide number of ways for law enforcement to gain access to individuals phone pictures, texts, call history and video stored on past iphones.
What has changed with the latest Iphones is an Encryption that the FBI has not been able to decrypt.