The Xiaomi Redmi 3 runs on MIUI 7, which utilizes an Android 5.1.1 Lollipop core. MIUI 7 brings its take at the interface and improves on its performance. According to Xiaomi's changelog, MIUI 7 is 30% faster and more responsive and 10% more energy efficient. It also adds a few new things as a baby album, child mode, new default themes and auto DND option.
As usual, Xiaomi's customizations run very deep and replace everything including all Google services. In fact, the Mi phones sold in China don't have access to Google's services and those need to be sideloaded one way or the other (some resellers may even do that for you). The models sold officially in markets outside of China come with a preloaded Play Store app.
The lockscreen has a clock in the top left corner - gone are the lockscreen widgets. To unlock the phone, you swipe upwards and if you want a quick access to the camera - just swipe from the right side.
Beyond the lockscreen is the Android homescreen with four customizable shortcuts docked at the bottom by default, but you can dock up to five items. You can have any app there or even folders with multiple items if you will.
There is no app drawer - anything you install pops up on your homescreen, which can have unlimited panes. There are no shortcuts, and the usual routine of removing icons (dragging them up to a recycle bin at the top of the screen) will uninstall the corresponding app. There is a pop-up for confirming the action, though, so you can't accidentally uninstall apps.
Homescreen widgets are available, too - tap and hold on the homescreen, and then choose Widgets. There are few options available, but of course, you can get even more from the Play Store.
Homescreen effects are available, and you can change themes, too. A theme will change your homescreen wallpaper, lockscreen style, system icons, system font and the sound profile (you can disable changing the sound profile from settings).
MIUI v.7 introduces five default themes - MIUI, High Life, Pink Blush, Rose, and Ocean Breeze, but you can always download new themes from the Mi Store.
The notification area has two semi-transparent tabs - the first one hosts all notifications while the second one (swipe left to access) offers (customizable) quick toggles and a Settings shortcut.
An enhanced task switcher with Clear All option is available, too.
By the way, Xiaomi's proprietary Search widget does a similar job as iOS's Spotlight system-wide search. You can fire it up by swiping up anywhere on the homescreen. The tool searches through your apps, music, email, settings, among others.
Xiaomi provides its cloud service for content syncing between devices. Each Mi Cloud account gets 5GB of free storage. You can use it to backup contacts, messages, your entire gallery, calls log, notes, settings, voice recordings, Browser content (history, tabs, web app data) and your music library.
Xiaomi's sync and backup service share lots of similarities with the Apple iCloud. There is even a free Cloud Messaging option that allows you to exchange messages with other Xiaomi owners.
Finally, if you signed in with your Mi Cloud account, you can opt for the Find device feature - a handy feature in case you misplace your Xiaomi Redmi 3 or someone steals it.
MIUI 7 has a new Child mode, which once setup, allows the limited user to run only specific apps. This is nice if you have a kid, who likes playing with your phone occasionally, and you are afraid it might delete some important data.
The Do Not Disturb mode has been enhanced too - it supports better customization and scheduling options.
We did get our review unit with pre-installed Google Play Store plus Google sync for app data, contacts, and browser data but perhaps they've been sideloaded by the reseller providing this review unit. Of course, you can sideload them yourself one way or the other if they don't come pre-installed on your unit. And once you have those, you can easily download all other Google apps such as Google Now straight from the Play Store.
The Redmi 3 is Xiaomi's second smartphone to come with a locked bootloader. According to a recent official statement, the company will be locking the bootloaders of all upcoming models as required by Google's CTS (Compatibility Test Suite).
Xiaomi is providing a proper tool for official unlocking of the bootloader for the users, who like to tweak their devices further. This may also require switching your official 'stable' ROM to a developer one. Note that the page is in Chinese only. It also requires you to be a member of specific status over at the Mi forum.