Turn SIM PIN Lock On or Off
Every restart of your Xiaomi phone stops at a PIN prompt before you even reach the pattern or code unlock screen. If you already trust your environment and that extra step feels redundant, MIUI lets you disable the SIM PIN lock for each card individually. On a dual SIM device, forgetting which slot still has it active is a common source of confusion.
Turn Vibration on Tap On or Off
Every tap on your Xiaomi screen can trigger a short buzz, and if that feels too strong or barely noticeable, the haptic feedback setting is usually the cause. MIUI lets you switch this tap vibration off completely or pick between three intensity levels. The same control also affects the buzz you feel while typing on the keyboard.
How to Turn on/off Airplane mode
If your Xiaomi phone suddenly stops receiving calls, texts, or mobile data, Airplane mode is often the reason. Turning it on shuts down the mobile network, mobile data, WLAN, and Bluetooth at the same time. On some Xiaomi phones you can still switch WLAN or Bluetooth back on manually while Airplane mode stays active, which causes confusion when connectivity only half works.
Turn On/Off Contact Suggestions
When Contact suggestions are active on a Xiaomi phone, the keyboard pulls names, numbers and email addresses from your Contacts app while you type messages or fill out forms. That can be handy for quick replies, but it also means personal details from your address book show up as autocomplete hints in apps that have nothing to do with Contacts. If you want tighter control over what your keyboard suggests, this setting is the one to check.
Set Up a Private DNS Server
If your Xiaomi phone still resolves domains through whatever DNS your carrier or Wi-Fi router assigns, you get no ad blocking, no tracking protection, and inconsistent speeds between networks. On some models the Private DNS option is missing entirely or resets to Automatic after a reboot, which silently stops a custom provider like Cloudflare or Google DNS from taking effect.
Change Default Messaging App
Texts land in one app while replies keep opening in another, or a new SMS app you downloaded from the Play Store never becomes the one that actually launches. This happens because MIUI keeps a fixed default assignment for messaging that does not update automatically when you install a new app. Until that assignment is changed manually, notifications and quick replies keep routing to the wrong app.
Assign a Custom Ringtone to a Contact
If every incoming call sounds the same, you have to check the screen to know who is calling before you pick up. On Xiaomi phones, the default ringtone applies to all contacts unless you override it manually for specific people.
Change Call Waiting Notification Sound
If the call waiting tone plays continuously instead of just a short beep, or a second incoming call barely gets your attention, the notification style set for call waiting is likely the cause. Xiaomi phones let you pick between a single tone, a repeating tone, or a tone combined with vibration, and the wrong choice makes overlapping calls easy to miss or annoying to handle.
Set a Custom Ringtone for Calls
If your Xiaomi phone still rings with a stock tone and you want a favorite song for incoming calls instead, the built-in ringtone list only shows preset options at first glance. MIUI actually lets you pick any audio file already stored on your phone, without moving it into a dedicated ringtone folder. On dual SIM devices, the ringtone also needs to be set separately for each SIM card.
Turn On/Off Call Forwarding
Calls landing in voicemail even though your phone never rang usually means call forwarding is already active in the background. On many Xiaomi phones the network sets forwarding for 'busy', 'unanswered' and 'unreachable' cases by default, so you might not notice it until a call disappears. Each of these forwarding rules can be switched on or off separately, or redirected to a different number entirely.
Change Keyboard Height
If the on-screen keyboard on your Xiaomi phone feels cramped for typing or covers too much of the screen, the Keyboard height setting is usually the cause. MIUI offers seven size presets from extra short to extra tall, and picking the wrong one makes typos more likely or blocks content you need to see while typing.
Turn MIUI Optimization On or Off
If your Xiaomi phone feels sluggish after enabling developer options, or certain apps crash or render oddly, the 'Turn on MIUI optimization' toggle inside developer options might be the cause. This setting controls how MIUI's custom interface layer interacts with the underlying Android rendering engine. Switching it off can fix app compatibility problems but also changes how some system apps look and behave.
Enable or Disable LED Notification Light
If your Xiaomi phone stays dark when a new message arrives, the LED notification light might be switched off for that app. This setting works per app, so one app can flash the LED while another stays silent. Not every Xiaomi model has a physical LED, so the option may be missing entirely on some devices.
Change App Lock Settings
Once App lock is turned on for an app, MIUI still leaves several details open: notification previews can leak private messages, protected apps might each demand their own unlock, and Xiaomi keeps suggesting more apps to add to the lock. These behaviors come from separate switches inside the App lock settings, not from the lock feature itself.
Forget Saved Wi-Fi Networks
If your phone keeps reconnecting to a slow or wrong Wi-Fi network instead of your home connection, an outdated saved entry is usually the cause. This often happens after a router password change or when two networks share the same name. Removing the old entry forces your Xiaomi phone to ask for the current password the next time it connects.
Route a Contact Straight to Voicemail
When a specific contact keeps calling at bad times, you do not have to reject the call manually every time. MIUI lets you route calls from a single contact straight to voicemail while everyone else still gets through as normal.
Block Calls from Unknown Numbers
When a caller shows up as Unknown or Private, your Xiaomi phone has no caller ID to check against a blocklist entry. Instead of rejecting these calls by hand every single time, you can have the Phone app reject them automatically before they ring through.
Add a Fingerprint
If you can only unlock your Xiaomi phone with one specific finger, you probably registered just a single fingerprint during setup. MIUI lets you store several fingerprints so both your left and right hand work for unlocking or confirming payments. Each saved fingerprint can also get its own name, which helps when the device is shared with family.
Turn Call Barring On or Off
If your Xiaomi phone keeps racking up charges while roaming abroad, or you need to stop all incoming or outgoing calls for a while, call barring is the setting responsible. Unlike silencing a contact or using Do Not Disturb, call barring blocks calls at the network level and requires a password to change. Getting the wrong option enabled can also cut off calls you actually want, like international or roaming numbers.
Turn Auto-capitalization On or Off
If your Xiaomi keyboard keeps capitalizing letters you want lowercase - like usernames, code snippets, or crypto addresses - auto-capitalization is likely running in the background. It automatically capitalizes the first letter after a period or new sentence, which speeds up regular typing but gets in the way for technical text. The setting sits inside the keyboard's text correction options, not the main system settings.
Manage App Permissions
If you tapped Deny when an app first asked for camera or contacts access, that app stays locked out until you change the setting yourself. MIUI does not repeat the prompt later, so features like document scanning or contact sync can quietly stop working. The permission is not deleted, it just needs to be switched back on in the app settings.
Turn On/Off Long-press for Symbols
If numbers, accents or special characters only appear after holding down a key on your Xiaomi keyboard, Long-press for symbols is doing its job in the background. When this setting is off, those hidden symbols stay invisible and you cannot access them at all through a long press. The delay before a symbol gets inserted can also feel too short or too long, depending on how you type.
Block Apps from Using Mobile Data or Wi-Fi
If an app keeps burning through your mobile data plan even though you are connected to Wi-Fi, a per-app network permission is likely still letting it use the mobile connection. Xiaomi phones let you lock individual apps to just one connection type, which stops unexpected background data use. This helps with apps you only want active when Wi-Fi is available, or that should never touch mobile data.
Show or Hide Carrier Name on Lock Screen
If your Xiaomi lock screen shows the SIM carrier name under the clock, a MIUI status bar setting is behind it. Some people want that text gone for a cleaner lock screen or extra privacy, while others lose it after a reset and want it back. Either way, the toggle sits in one specific settings screen and is easy to miss.