Pros
Cons
Our Verdict
At the office, I have a MacBook Pro hooked up to an 1TB LaCie drive. I’ve partitioned that external into two volumes: one for Time Machine, the other for maintaining a bootable clone of the MacBook’s hard drive.
Such a setup is not particularly unusual. Nor is the minor hassle of disconnecting that drive from my MacBook whenever I want to take the laptop to a meeting or home: I switch to the Finder, scroll down to the Devices section of the sidebar, click the Eject icon next to one of those external volumes (or, if I remember, press Command+E), then click the Eject All button in the subsequent dialog box. If I forget to do all that, I’m rewarded with two more dialog boxes chastising me that the volumes were not ejected properly.
As I say, in the grand scheme of things, the process is a minor hassle. But I unmount (or forget to unmount) those two volumes frequently enough that the hassle turns into a headache. I’d like a quicker, easier way to unmount external volumes without giving OS X fits.
I’m apparently not alone: The problem is widespread enough that several Mac utilities have cropped up to solve it. I’ve come to like a relatively new offering, Appgineer’s $6 Mountain ( Mac App Store link, though see the note below about buying from the Mac App Store).

Mountain installs as a menu-bar utility with an icon that looks much like the Finder’s Eject button. Click that icon, and you see a list of your Mac’s internal and external volumes (with the latter including any servers you’re currently connected to); click the eject button next to one to immediately unmount the volume. The menu also lists volumes that you’ve recently connected to, with the eject icon cleverly turned upside down; you can click one of those upside-down icons to remount the associated volume.
Mountain’s menu also includes an option to connect to a server (which opens the Finder’s Connect to Server dialog), as well as Unmount All And Sleep. The latter option is the one-click solution I’ve been looking for: It unmounts all connected volumes (except your startup drive, of course) and then puts the computer to sleep. You can even configure keyboard shortcuts to unmount external drives, unmount and sleep, mount unmounted volumes, and mount your favorite servers (which you also designate in the preferences window).
You can customize Mountain in a bunch of other ways, too. There are options to hide internal volumes (since you’re less likely to want to unmount those); hide system volumes (ditto); and—particularly handy—hide unmounted volumes. You can also opt to automatically open newly mounted volumes in the file manager of your choice. (The app includes Finder alternatives, such as PathFinder, in its list if you have them installed.)

You can also set alerts to notify you when volumes become available or are unmounted, and when it’s safe to unplug an external volume. And you can customize the app’s behavior for each disk you use—opting to prevent unmounting of a particular volume altogether, for example, or to unmount all partitions of a particular disk when one of its volumes is ejected.
The thing I like best about Mountain, though, is that it offers all these customizable options, yet it remains essentially simple to operate. You can set it up to work the way you want, but when it comes time to unmount a disk, you still just click a single button or hit a single keyboard shortcut.

As I say, there are several alternative apps that do much the same thing, some of which offer functionality that Mountain doesn’t. For example, Jettison can be set up to automatically eject external drives when you close your laptop’s lid; FreeSpace shows you how much free space is available on each attached volumes; and unDock lets you run AppleScripts when you unmount a drive. But I don’t think they offer the same degree of customizability and well-rounded functionality that Mountain does.
If you regularly attach external volumes to your Mac laptop, and you’re tired of forgetting to properly unmount them, Mountain could make your life just a little easier. For $6, it’s a relatively affordable solution to a minor, but ultimately vexing, problem that bugs a lot of Mac users.
(Note that Mountain is currently available both from the Mac App Store and directly from the vendor’s website. Due to the Mac App Store’s sandboxing requirements, the Mac App Store version doesn’t have all of the same features as the direct version, so I recommend purchasing directly.)
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