GRUB - Multiboot boot loader
EasyBCD - EasyBCD is NeoSmart Technologies multiple award-winning answer to tweaking Windows bootloader.
Grub2Win - Safely dual boot Windows and Linux without touching the Windows MBR.
Systemd-Boot - Systemd-Boot, formerly known as Gummiboot, is one of the simplest UEFI boot managers that lets you boot Linux and Windows in EFI mode even if the system is BIOS only supported.
EasyUEFI - Manage EFI/UEFI Boot Options & Manage EFI System Partitions & Fix EFI/UEFI Boot Issues
U-Boot - Das U-Boot (the Universal Bootloader) and Embedded Linux