.THUMBDATA4 File Extension
What is an .THUMBDATA4 file?
.THUMBDATA4 is Google Android thumbnail database
The thumbdata4 file extension is associated with the Android, an operating system based on Linux kernel developed by Google for smart phones and tablets.
The thumbdata4 stores temporary thumbnail database generated by Android for pictures and other multimedia content stored on the phone's local data storage, or SD card.
Behind thumbdata4 extension are two dashes "--" and number generated randomly depending on the device or something else.