Hands-on with leaked Android 4.3 ROM for the Google edition Galaxy S4 [Updated]

First glimpse of the next version of Android looks a lot like what's come before

There's a leaked Android 4.3 Jelly Bean ROM out in the wild this morning, in the form of a pre-release build for the 'Google Play edition' Galaxy S4. It's also been ported to the European LTE Galaxy S4 (GT-i9505) in the form of a custom ROM, courtesy of the original source of the leak, Samsung fansiteSamMobile.

We've fired up that ROM on our European GS4 and shot a quick hands-on video, giving an early glimpse of the next version of Android. And, well, it looks an awful lot like the current version of Android, supporting earlier reports that 4.3's changes are mostly under-the-hood, rather than user-facing. That means for the most part, we're dealing with the same user experience found on the current Google Play edition GS4.

Check out our video after the break, along with a list of behind-the-scenes changes we've noticed.

Under-th​e-hood changes

Here's a quick run-down of some of the new stuff we've spotted in the leaked 4.3 ROM. Starting with the nuts and bolts —

• We're seeing "android.hardware.bluetooth_le" listed as a feature in the Android System Info app, suggesting Bluetooth Low Energy support is on-board in Android 4.3, as previously reported. (This feature isn't listed on our Google edition GS4 review unit running Android 4.2.2).
• Similarly, Bluetooth tethering is present in the 4.3 ROM, while it's absent (bizarrely) on our 4.2.2-based GS4 GE review unit. Other phones like the Nexus 4 have it on 4.2.2.
• A new checkbox under Advanced Wifi settings allows Google's location service to scan for Wifi networks even when Wifi is turned off and not being used for wireless networking — likely part of Google's new approach to battery-friendly location services.

In Developer options...

• Multiple options under "Monitoring > Profile GPU Rendering," as seen in this Google I/O video. This lets you view a graphical representation of the time taken to generate a frame, and see whether you're hitting the 60 frames per second target or not. This should help devs create more buttery apps.
• New debug options for the new non-rectangular clipping feature. This is a new graphical capability for devs in Android API level 18.
• A new option to "Use experimental WebView" — this likely changes the browsing engine used to handle websites within apps, but we haven't been able to nail down exactly what it does.
• There's also a button that lets you "Revoke USB debugging authorization." This deletes the RSA key generated for USB debugging authorization from the phone itself — previously you had to do this from the computer side.

Phone and Messaging...

• By pressing menu in the phone app, you can now add two-second pauses in your dialing string (denoted by a comma) or longer waits (denoted by a semicolon.)
• In Settings in the phone app, you can now enable dial-pad autocomplete and change DTMF (dual-tone, multi-frequency) tone lengths.

Other bits...

• There's the new c--amera app we talked about in our earlier post.
• Long, multi-word SSID names now wrap properly down to a second line in the quick-settings pulldown.
• When you take a screenshot and share it via email, the Subject field is automatically populated with the date and time of the shot.