D64 Navigator is a simple multi-function file explorer, such as DOS Navigator or Norton Commander was in the past. Its main objective is that you can manage D64 files:
If you press F1 on a D64 image (or when you are in it), you can see (and edit) BAM (Block Availability Map):
You can make different type of D64 disk image, only click on F2:
With the help of the file editor (F4) you are able to alter only one or more bytes:
You can set the file associations if you click on the cog and D64Navigator will open files with the given applications, except D64 and TAP of course:
You can read TAP files (by Kernel, Nova and Boot loaders) and copy the contents of them to a PC folder:
...or to a D64 disk image: