A message concerning the bootloader and the security of the device appears at each boot of certain iodé phone models. This message indicates that the bootloader is unlocked. Indeed, the bootloader is a program used to launch or install an alternative operating system, and must be unlocked by iodé beforehand
Your data on your iodé smartphone is encrypted following ‘File-Based Encryption’. Only you could decrypt using your lock password or schema and access your data, even if you lose your phone. An unlocked bootloader will only let a malicious person with few programming skills access ‘fastboot’ commands or the ‘recovery’ program and install a new operating system. Your data will not be accessible.
A few manufacturers like Fairphone allow bootloader relocking. If you order a iodé Fairphone 3+ or 4, the bootloader is therefore locked.