Android 5.1.1 vs 6.0.1: Key Marshmallow Upgrades Over Lollipop
Android 5.1.1 is the final revision of Lollipop, while 6.0.1 is the first maintenance release of Marshmallow, adding granular permissions, Doze battery savings, and native fingerprint support.
People often confuse them because both rolled out quietly as OTA “bug-fix” updates; carriers buried the version number in tiny text, so users just saw “system update available” and tapped without noticing the jump from Lollipop to Marshmallow.
Key Differences
Marshmallow lets you allow or deny a permission—camera, mic, contacts—per app, whenever it asks. Doze stretches standby battery by hours. USB-C, adoptable storage, and Now on Tap search inside any screen are also 6.0.1 exclusives.
Which One Should You Choose?
If your device officially offers 6.0.1, install it; security patches ended for 5.1.1 in 2016. On legacy hardware, weigh the smoother Lollipop UI against missing patches, or flash a lightweight 6.0.1 ROM if available.
Examples and Daily Life
Imagine getting a WhatsApp call on 5.1.1—it can grab your mic without asking. On 6.0.1, a popup appears: “Allow microphone?” One tap grants it; deny once and the app stays muted until you change your mind.
Can I downgrade from 6.0.1 to 5.1.1?
Only if you unlock the bootloader and flash an official 5.1.1 factory image, wiping data in the process.
Does Doze work if I leave Wi-Fi on overnight?
Yes. Doze triggers when the phone is motionless and idle, pausing network sync until you pick it up again.