In our review of the Nexus 10, our single biggest gripe about the device was that the Android's tablet ecosystem continues to lag behind that of iOS, despite its nearly two years on the market. With Ice Cream Sandwich and Jelly Bean, Google has done a good job of keeping pace (and exceeding) the competition on the first-party front, but third-party Android apps are all too often just phone apps scaled up, with no adjustments made for larger 7-inch and 10-inch screens.

But what makes a good tablet app in the first place? And what are we complaining about, specifically, when we say that Android's tablet apps are usually inferior to their iOS counterparts? The deficiencies are both aesthetic and functional—the best tablet apps not only make changes to look better than the worst ones, but they also use that extra screen space to enable (or simplify) common activities that aren't possible on a smartphone's smaller screen.

I am not going to attempt to call out every bad tablet app, nor will I try to point out every good one. Instead, I'll choose specific, widely used apps that exemplify the worst things about Android tablet apps and highlight some of the changes (small and large) that could be made to improve them.

Dropbox: A serious case of wasted space

The Dropbox for Android client's layout is one that makes sense on a phone, and it's really very similar to what the app looks like on iOS: you're presented with a big list of all your files and folders, along with some basic top-level navigation options for searching and accessing starred files. Tapping one of the folders will take you to that folder, and you can only view all of the contents of a single folder at a time.

The worst thing about this app, both functionally and visually, is the vast expanse of unused white space. Something like this isn't quite as noticeable on a 7-inch tablet, but the more space you have, the more space is wasted. For apps with a focus on navigating through files, one of the smartest ways to utilize a tablet's extra space is to add more navigation options. The Google Drive app, which takes its design cues from the generally good Gmail app, is a good example of this:

Google Drive puts a persistent file navigation bar to the left so that even as users wander through their files and folders, they have an easy-to-see-and-access anchor to the top level of the drive. The Box app for Android is similar, though it doesn't allow you to preview images or documents, preferring rather to use Android's Intents system to kick these files to another app that can read them.

The persistent navigation sidebar doesn't necessarily improve the functionality of the app, though—Dropbox for Android does have a few persistent navigation buttons, though they aren't as easily accessible or as readable. To show how the Android app could be made better, let's look at Dropbox for iOS.

On the left side of the iPad's Dropbox app is something functionally similar to the company's iPhone app: a list of files and folders you can scroll through, along with some fixed navigation buttons on the bottom.

Where the iPad's Dropbox app goes above and beyond both the Android version and the Google Drive app is in its use of the right side of the screen, which serves as a giant preview pane that you can use to view your documents and images, all while the file explorer on the left side of the screen sticks around. It's a little thing, but the lack of windowed multitasking in most touchscreen operating systems means that you have to give people the ability to do multiple things any way you can. The iOS Dropbox app accomplishes this; the Android app does not.