The second generation Nexus 7, revealed a few weeks ago, is a good refresh of this popular Android tablet. Beside the much improved display density (going to 323 ppi from 216 ppi), this all-new Nexus 7 also has a different system on chip (SoC). If this tablet is used mainly for browsing the web, how does it perform compared to its older sibling?
Let's take a look at the hardware specification differences, which may contribute to the performance. The memory has been bumped from one GB to two GB, which provides much more breathing room for applications (notably the web browser). The SoC is still a quad-core system, Nexus 7 2012 uses a 1.2 GHz Nvidia Tegra 3 while the 2013 edition is based on a 1.51 GHz Qualcomm Snapdragon S4 Pro (APQ8064). The latter is a little confusing (probably just a branding issue) since it is more like an underclocked Snapdragon 600, with a Krait 300 CPU.
Comparing these two SoCs, this battle can probably be viewed as a match between the implementations of ARM Cortex-A9 MPCore (Tegra 3) versus ARM Cortex-A15 MPCore (APQ8064). It would be interesting to see how APQ8064 competes with some new Tegra 4-based tablets.
Now it's time to see some colorful bar charts. Note that every test is carried out on the respective device running Jelly Bean (Android 4.3) and with Chrome 28.
The first test is DOM performance. A fast implementation of DOM modification and access will significantly impact many web pages that sprinkle in some interactivity. Using the collection of DOM core tests from Dromaeo, here is the result (longer is better). The new Nexus 7 definitely shows approximately 20 percent improvement compared to the older generation.
With another benchmark from Mozilla, Kraken, the outcome looks pretty similar (shorter is better). Kraken itself aims to resemble future-generation web apps. In this category, Snapdragon S4 Pro demonstrates a major win (more than 50 percent) over the poor Tegra 3 system.
While it is not covered here, there is also a GPU difference that can make an impact. The new Nexus 7 is equipped with an Adreno 200. According to the various graphics benchmarks done by AnandTech, this easily kicks Tegra’s ULP GeForce to the curb. A faster, better GPU is always a good thing for web browsers, particularly for rendering-heavy web applications that can use a lot of GPU compositing benefits.
From our previous quick check of the 2012 edition of Nexus 7, its web performance is more or less comparable to the iPad 3. It's good to know that Google raises the bar again and pushes for a more performant, affordable Android tablet for all of us!
Verdict: Using Nexus 7 mainly for web browsing and the cost is not a problem? Upgrade.
Note: Special thanks to Donald Carr for a short loan of his Nexus 7.