Android 4.3 Jelly Bean has been popping up recently in the form of leaked firmware for older Samsung devices as we wait for official rollouts which are expected to begin in October.

SamMobile shared Android 4.3 test firmware for the Samsung Galaxy S4 on Tuesday. The build version I9505XXUEMI8, available for download for the GT-I9505 model of the Galaxy S4 is said to be stable and bug free. With the Android 4.3 firmware come such apps as Samsung Knox and Samsung Wallet. SamMobile reports that performance has improved greatly with Android 4.3 on the Galaxy S4, with lags having diminished in comparison to Android 4.2.2. In addition Android 4.3 brings to the Galaxy S4 an updated Reading Mode and keyboard, color reproduction, which allows for sharper text and other minor UI changes.

Android 4.3 test firmware for the Galaxy Note 2 was then leaked by a forum member on Wednesday.  The build version N7100XXUEMI6 is available for download for the GT-N1700 model of the Galaxy Note 2, and is notably the first Android 4.3 leak for the Galaxy Note 2. Reports indicate that Samsung just recently began testing Android 4.3 for the Galaxy Note 2 so the leaked build is believed to be an early one and bugs are to be expected. Like the leaked Galaxy S4 build, N7100XXUEMI6 includes Samsung Knox and Samsung Wallet and has implemented UI elements already seen on Galaxy S4 and Note 3. The Android 4.3 update for the Samsung Galaxy Note 2 is expected to include even more features by the time its ready or an official release.

While we don’t recommend installing such firmware onto your Galaxy S4 or Galaxy Note 2, they are available. Those who wish to flash either build should do so with caution and back up their handsets beforehand.

Android 4.3 test firmware for Samsung Galaxy S4 information and download.

Android 4.3 test firmware for Samsung Galaxy Note 2 information and download.

Keep in mind that there have been several indications that Android 4.3 will soon officially roll out onto older handsets such as the Samsung Galaxy Note 2, Galaxy S4 and Galaxy S3. Samsung confirmed that the Galaxy S4 and Galaxy S3 would update to Android 4.3 in October, while recently, a French carrier announced updates for the Galaxy S4 in October and the Galaxy S3 and Galaxy Note 2 in November.

Many expect that the rollout schedule for the Galaxy S4, S3 and Note 2 pertain to international versions of those handsets. U.S. models may not see an Android 4.3 update until much later due to the carrier specific testing and certifications required for system updates to roll out in the U.S.

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