If you're constantly using USB memory devices and external drives to transfer information between computers, this little tool can be really useful for you.
Zback lets you synchronize files between folders, either on the same computer or between different drives – which includes different computers and also USB devices. Being a standalone app that doesn't require installation, you can carry Zback always with you on a USB stick and use it whenever you need it.
Zback features different syncing and backup modes and can also filter files by size, date or name for more accurate results. It also supports working in batches, which comes in handy for repetitive syncing tasks.
That said, the truth is that Zback is not certainly the most intuitive program in the world. The interface is a bit confusing and it takes some time to get to grips with it. Fortunately each button displays a little text hint when hovering the mouse.
Though it could be improved in terms of usability, Zback is still a handy app to synchronize contents between folders and drives.