Android 6.0 Marshmallow made its debut on the Nexus 5X and Nexus 6P, the first time we've seen two smartphones launched alongside each other in the Nexus programme. 

Marshmallow has also made its way to other Nexus devices, including the Nexus 6, Nexus Player, Nexus 9, Nexus 5 and the Nexus 7(s). It will soon be rolling out, skinned, to other devices too.

If you're feeling a little lost, or want to unlock Marshmallow's secrets, then we're lining up a full Android 6.0 Marshmallow guide so you can find all those sweet features.

It's worth remembering that manufacturers will have their own take on Marshmallow. Some features might be reserved as they are here, and some will not.

Enable developer settings: To turn on the developer settings, head into Settings > About phone. Scroll to the bottom and tap on the Build number. After a number of taps, you'll unlock the developer options.

Unlock System Tuner UI: This is a clever hidden setting that offers a range of options you can't otherwise get to. You have to first enable the developer settings (as above). Then you swipe down the Quick Settings and press and hold the settings cog at the top next to the battery. After a long press, the System Tuner UI will be unlocked, and a new option will appear in the settings menu.

Show the battery percentage: Once you've unlocked the System Tuner UI (as above), you have the option to show the battery percentage in the battery icon at all times. (Most third-party skins have this as a default option.)

Turn on ambient display: A feature of Android Wear and Motorola devices, it's now on Android 6.0. Head into Settings > Display and you'll be able to glance at monochrome notifcations.

Quick launch the camera: (Nexus 5X and Nexus 6P only) Head into Settings > Display and there's the option to quick launch the camera with a double press of the standby button. It's much faster than unlocking your phone and hitting the icon.

Play Flappy Android: Marshmallow's Easter Egg is an Android take on Flappy Bird, as it was in Lollipop. Head into Settings > About phone/tablet > Android version. Then tap the Android version repeatedly until it changes to the Marshmallow screen. Once you have the full Marshmallow wording visible, press and hold. You'll flip into the Flappy Android game. Enjoy!

Search settings: Rather than rooting through everything, you can search the settings. Just open up the Settings menu and hit the magnifying glass and type what you're looking for.

Use Now on Tap: Just press and hold the home button. If you're looking for theb settings, go into Google Now > Settings > Now cards and you can enable or disable Now on Tap.

Find the Google Settings: There was previously an app to handle Google settings, in Marshmallow this is now in the main Settings menu. This is where you'll find settings for accounts and services, backup, and transferring content to a nearby device.

Use Flex Storage: If you have Marshmallow and a microSD card slot, you can turn that external storage into integrated internal storage. Head to Setting > Storage & USB. At the bottom you'll see the SD card details, with the option to format and use as internal storage. You then get to manage and move content to this partition once done.

Use the native file explorer: There's now a file explorer in Android. Head to Settings > Storage & USB and scroll to the bottom of the list. Tap Explore and you can view folders, open files, delete and share.

Stop adding new app icons to homescreen: If you don't want new apps you install cluttering up your homescreen, head into Play Store > Settings and uncheck the box.

Add Yahoo! Mail to Gmail: You can add Yahoo! or other mail services to Gmail. Tap the icon to open the sidebar, scroll all the way to the bottom and hit Settings > Add account. You have the option for Google, IMAP/POP3 services (like Yahoo, and Exchange.

Attach anything to Gmail: Tap the attachment button and you can attach local files, things in Drive, Photos, Dropbox files, OneDrive box and so on. It's really flexible.

Limit Drive-enabled apps to Wi-Fi sync only: To save yourself a data bill, head into the Google Settings app > Drive-enabled apps and turn on Wi-Fi only. Alternatively, if you need it to sync on a cellular connection, switch it off!

Customise Google Now: Tap the settings icon that appears in the search bar. Here you can select the content you want to see, as well as change the settings, or place reminders.

Turn off backgrounds in Calendar: Don't like the seasonal backdrop in your new calendar? Head into Settings and tap the slider to turn it off.

Change the default app: Android lets you decide which is the default app, if you have more than one that will do the same thing. Under Apps, select the app, and hit "open by default". Here you can clear defaults so you can change to another app for those tasks.

Control app permissions: Marshmallow lets you manage all the permissions for each app on an individual basis. Go to Apps and select the app and hit Permissions. This will let you toggle permissions on and off, so you can disable location access, for example.

READ: Android 6.0 Marshmallow review

Quickly switch to vibrate alerts: If you want silence, but are after vibration alerts still, then push the volume button and tap the bell on the pop-up. This will switch to vibrate.

Turn down media volume: Hit the volume up or down button, and the volume slider will appear. Tap the down arrow on the right-hand side, and you can change the ringer, media or alarm volumes.

Engage Do not Disturb: Swipe down Quick Settings and tap the Do Not Disturb button. This gives you the option to have total silence, alarms only, or priority only. You can choose if this is for a time period, or until you turn it off.

To mark an app as a Priority app: Head into Settings > Apps. Tap on the app you want. In Notifications you get app controls, and you can set an app as a priority so you always get notifications from that app.

To turn off notifications on an app: Go to Settings > Apps > Tap on the app you want. In Notifications you can block all notifications for any app on your device.

To turn off peeking on an app: Go to Settings > Apps > Tap on the app you want. In Notifications you can turn off peeking, so you don't get a toast notification for that app.

Instant access to lockscreen notifications: Just tap a notification twice and it will open up the app. Want to dismiss it? Just swipe it away.

Pinch to expand: Got a stack of notifications? You can pinch to expand them, both on the lockscreen and in the notifications area.

Hide sensitive information in lockscreen notifications: You can have lockscreen notifications without to much information being revealed. Head to Settings > Sound & notification > App notifications, to manage apps with sensitive information.

Then go to Settings > Sound & notification > When device is locked, to change the information revealed. This will then ensure that all apps you've marked up don't give anything away.

Quickly select a Wi-Fi network: Swipe down for Quick Settings, then click the network name beneath the Wi-Fi icon. This takes you through to the Wi-Fi settings. 

Quickly manage Bluetooth: The same applies to Bluetooth. Click beneath the Bluetooth icon in Quick Settings and you'll head into settings to select your device.

Turn on torch/flashlight: There's no need for a separate app, just tap the button in Quick Settings to turn on your flash as a torch. Or just say "Ok Google, turn on torch/flashlight" and it will turn on.

Cast your screen: Want your Android device on your TV? Just swipe down and tap Cast screen and it will be sent to your Chromecast. Not all apps are supported though.

READ: When is Android 6.0 Marshmallow coming to my phone?

See your battery percentage: Open Quick Settings with a two-finger swipe. Your battery percentage is displayed here. Or enable it through the System UI Tuner, as detailed above.

Time till fully charged: Charge time is displayed when connected to a charger. Look at the bottom of the lockscreen and in the battery status screen, but it takes a little while for Android to calculate how long charging will take. If you're fast charging, it will say "charging rapidly"

See what's eating battery: Swipe down Quick Settings, tap the battery icon. You'll go to the battery status page and see how long you have left and what apps are eating your battery.

Turn on power saver: In the battery status page, tap the menu button, select power saver. You can elect to have to automatically switch on at 15 per cent or 5 per cent battery. The system bars turn orange when it is on.

Limit what users can see: Create a restricted profile by tapping Settings > Users > Restricted profile. You can then limit what your children can access, for example. 

Guest profile: In the same area (Settings > Users) you can create a Guest profile. While it is setup, you'll get the option to access as a guest from the lock screen.

See how much storage they're using: If you want to know how much space is being used up by another profile, head into Settings > Storage. At the bottom of the list it says how much other profile and the guest is using.

Instant lock: In Settings > Security there's the option to lock the device as soon as the screen goes to sleep. You'll find the option to lock as soon as you press the power button too. These are old settings, but really useful.

Manage fingerprints: Head into Security >Nexus Imprint and you'll be able to add or remove fingerprints that will unlock your device. A pro tip is to register fingers on both hands so you can unlock your phone with whichever hand you have free.

Bluetooth unlock: Again in Security > Smart Lock, you have the option to nominate trusted devices, so your Android will unlock when connected to something else. You can nominate Bluetooth devices (like your smartwatch or car Bluetooth) or select an NFC tag.