App recommendations - sync 2 drives

Can anyone recommend a good app (free or paid) that I can get that will allow me to make changes to files on one drive, and when I plug in the backup drive, compares the 2 drives and make drive 2 update to the changes I've made on drive 1?

Any program that allows incremental backups should do that job nicely. I personally use Carbon Copy Cloner for this but SuperDuper has this feature as well IIRC. I use these programs because they are capable of many other thing as well such as cloning your boot drive but there are many other programs that will do what you want.

Strictly speaking, Time Machine (TM), native to Macs does this.

If you have an iMac, you can keep the Backup (BU) Drive permanently attached - if a Tablet, and TM is activated, when the BU Drive is unmounted the Mac will prepare snapshots of any changes made and, on remounting the BU Drive, will update the latter.

No need to purchase or acquire any other app if that is your real objective.

(Of course the Cloning Software options are bootable and provide a second tier of BU options).

Ian

Also, Chronosync can do that as well.

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