Hex Editor works great

I just downloaded Hex Editor and it works great on my iPhone 6 Plus.
It has many useful functions like upload files via wifi to the phone from another device (This app acts as a web server). You can download directly from internet.
Search and replace bytes in hex.
This is exactly what I was looking for. Please if anyone writes a bad review specify your phone model and iOS version.

Jim Garrigues about HEX Editor