The Nexus 7 is the first tablet with Android 4.1 Jelly Bean, and the differences between Ice Cream Sandwich and Jelly Bean on tablets are a lot greater than Google first let on. For my comparisons with ICS tablets below, I used Samsung's Galaxy Tab 2 (which also has a custom overlay), Asus's Transformer Pad Infinity TF700, Acer's Iconia Tab A700, and Toshiba's Excite tablets (7.7, 10, and 13).
The changes are evident as soon as you start up the tablet and see the Welcome screen. The new Android 4.1 Welcome screen and its ensuing setup walkthrough and first-time-use pop-up explanations are incredibly friendly for newcomers, with big, bold lettering and a clean design. That clean design continues with the Android 4.1 home screen, which reflects numerous changes to the Android experience on a 7-inch tablet.
For one thing, Google has refreshed the home screen with changes both minor and dramatic. A nifty Google launcher runs along the bottom, with five basic Google app icons--for Play Books, Play Magazines, Play Movies & TV, Play Music, and the Play Store--and a folder packed with 11 other native Google apps, including the Chrome Web browser which now replaces the previous "Browser" app. At the center of this launcher bar is the new menu icon, which is the only one of the seven icons that's fixed; you can swap out the others for other apps of your choice, or for folders of apps you choose.
Google has shaken up the design of its core navigation and status buttons, in order to reorient everything around the portrait position. Google expects 7-inch tablets to be used more in portrait mode than anything else. This explains the move of the three nav buttons (back, home, and recent apps) from their former location flush left to their new locale, spread out along the bottom center of the display. The clock and notifications, meanwhile, move from the lower right of the display to the top of the screen. To gain access to the notifications or settings, you must slide down the "shader" from the top of the display. After the clean simplicity of the notifications pop-up on the lower right of the screen, this new design is hard to get used to. Pulling down the shader reveals a larger clock, a rotation lock soft-touch button, and a settings shortcut. Though cleaner than the pull-down Google provided on the early Froyo-based Galaxy Tab, the effect is the same: It makes the Nexus 7 feel more like a phone than a tablet.
Other interface tweaks contribute to making the Nexus 7 feel more like a giant phone than a tablet. The home and menu screens are fixed in portrait orientation, which can be jarring if you're moving from watching a video to doing something else on the tablet. And in the settings menu, you no longer have panes in portrait mode; this change makes it faster to navigate among settings options. Also gone is the battery life percentage; you get just an icon now.