Figures released Monday on developer.android.com showed Jelly Bean running on 37.9 percent of Android devices, with Gingerbread at 34.1 percent, followed by Ice Cream Sandwich at 23.3 percent, PC Magazine reported.
In June about 33 percent of Android users were on Jelly Bean, 25.6 percent were on Ice Cream Sandwich and 36.5 percent were on Gingerbread.
Part of the increase for Jelly Bean is down to two high-profile Android Jelly Bean devices that debuted in recent months: the Samsung Galaxy S 4 and the HTC One.
A reported 20 million Galaxy S4 devices have been sold.
Google is expected to release the next Android version, Key Lime Pie, in October, the fifth anniversary of the launch of the first Android-based phone.