iExplorer allows you to access your iPhone or iPad from its root ("/") directory, but this requires you to Jailbreak your device and may also require you to install afc2add or Apple File Conduit "2" from the Cydia app store. We recommend that only advanced users consider accessing files on their device from the root directory and be very cautious when making changes.
Without jailbreaking your device, you will still have read/write access to the Media ("/var/mobile/Media/") and Apps ("/var/mobile/Applications") directories in iExplorer. Additionally, you can also access a lot of other data close to the root in the Backup Explorer section under Backups.
NOTE: When connected to a jailbroken device and accessing it from its root directory, files that are created or modified may have the owner as "root." In certain cases, when attempting to modify these "root" owned files directly on the device through its apps, you may encounter various file access violations.
Additional Support Information:
Not finding your answer here? You can learn more about root folder access with iExplorer here: