Set Up a VPN Connection
If your company or university hands you server details instead of a ready-made VPN app, your Oppo phone needs a manual profile entered directly in the system settings. Without the right protocol, server address and login data, the connection fails silently or drops right after you save it. This is different from installing a VPN app from the Play Store, which handles the setup on its own.
Set Up Fixed Dialing Numbers (FDN)
If your Oppo phone dials out to numbers you did not approve, or a shared device keeps calling premium lines by mistake, Fixed Dialing Numbers can lock outgoing calls to an approved list. Incoming calls stay unrestricted, only outgoing numbers get filtered. The feature sits behind PIN2, which is easy to overlook in the carrier settings menu.
Turn Screenshot Gestures On or Off
If a screenshot pops up every time you swipe down with three fingers, or a partial capture opens whenever you touch and hold with three fingers, the screenshot gesture settings on your Oppo phone are active. These gestures work independently from the button combination and are enabled by default in ColorOS. Random captures while gaming or scrolling usually point to one of these gestures firing by accident.
Turn Screencast On or Off
If your Oppo screen does not show up on the Smart TV or another display, Screencast is often switched off or the target device is missing from the list of available receivers. Screencast mirrors your phone screen over the network, but it only works once the feature is enabled on the Oppo and the other device is discoverable. Without that active connection, nothing gets transmitted even if the TV is on and ready.
Change App Icon Style
If every app icon on your Oppo still shows the same rounded-square outline, the built-in icon shape picker probably has not been touched yet. Coloros lets you switch all home screen icons at once between styles like standard, material, pebble, or a custom outline. The setting is easy to miss because it sits inside general appearance options rather than the home screen settings themselves.
Change Default Messaging App
If Messenger or another chat app keeps hijacking your text messages, Coloros still only lets one app act as the default SMS handler at a time. Several installed apps can request that role, which is why replies to notifications sometimes open the wrong client. Oppo controls this behavior through a single setting in the app management area, separate from the messaging apps themselves.
Enable Vibration in Silent Mode
Switching your Oppo to silent mode also kills the vibration, so you miss calls and messages without any signal at all. ColorOS does not have a separate vibrate mode like stock Android, so silent and vibrate are tied together unless you change one setting. Once you know where to look, you can keep your phone quiet but still feel it buzz.
Turn On or Off Flip to Mute Incoming Calls
If your Oppo phone keeps ringing loudly during meetings even after you flip it face-down on the table, the flip-to-mute gesture might be turned off. This gesture silences an incoming call the moment the screen faces down, but only when it is enabled in the gesture settings. Some users also find the opposite problem: calls go silent unexpectedly whenever the phone lies flat.
Show Connection Speed in Status Bar
If you keep opening the data usage screen just to check how fast your connection is, Oppo can show that number right next to the signal icon instead. On Coloros this real-time network speed indicator is switched off by default, so the status bar only displays signal strength and battery. Turning it on adds a live Mbps or KB/s reading that updates while you browse or stream.
Turn On/Off Contact Suggestions in Messages
Typing a name into a message on an Oppo phone should pull up matching contact details automatically, but nothing shows up. This happens because the 'Suggest Contacts' feature inside the keyboard settings is switched off by default, even though the contact itself is saved correctly on the device.
Forget a Saved Wi-Fi Network
If your Oppo phone keeps reconnecting to an old Wi-Fi network with a wrong password or a router you no longer use, it is still sitting in the saved network list. ColorOS holds on to every network you have ever joined until you remove it yourself, which can cause slow reconnects or a jump to the wrong access point when two networks share a similar name.
Turn Always-On Display On or Off
If your Oppo screen stays completely black when locked, or notifications never appear on it, the Always-On Display setting is likely involved. This feature can show time, date and battery level permanently or on a schedule, and on newer ColorOS versions also notification icons. Whether it is active, and how much it shows, depends on a toggle that is easy to overlook in the display settings.
Allow or Deny Apps to Modify System Settings
If an app suddenly asks for permission to modify system settings, it usually wants to adjust things like your ringtone, brightness, or wallpaper, not your lock screen or passwords. On ColorOS this permission sits deep inside the special app access menu, so most users never find it on their own. Without it, some apps fail silently when they try to change these settings automatically.
Turn Keyboard Sound On or Off
Typing without any click sound, or suddenly hearing it after a system update, can be confusing since Oppo phones don't have a dedicated keyboard sound toggle inside ColorOS itself. The setting actually lives inside the Gboard app that most Oppo devices use by default. On many devices this sound is turned off from the start, leaving you unsure where to look for it.
Add App Shortcut to the Home Screen
On Oppo phones running the App Drawer layout, newly installed apps stay tucked away in the drawer instead of landing on the home screen. If you keep swiping up just to launch one app, you are missing a shortcut that needs to be placed there manually.
Personal Hotspot: Change Name, Password and Band
Your Oppo phone activates a personal hotspot with a generic name and a default password, which is fine for a quick test but risky for daily use. If you want other people to recognize your hotspot easily or you need a stronger password, you have to adjust these settings yourself.
Turn On/Off Emergency SOS
If pressing the power button five times keeps launching Emergency SOS by accident, or the shortcut refuses to trigger when you actually need it, the Emergency call quick access toggle is probably set the wrong way. The feature works straight from the lock screen and dials your saved emergency contacts, so an unwanted trigger during everyday use can be just as annoying as a missing one in a real emergency.
Turn Location (GPS) On or Off
When Smart Lock or Find My Mobile suddenly stops working on your Oppo phone, the location service is often the reason. Many apps also keep asking for GPS access even though you thought you had turned it off completely. Location tracking on ColorOS can be controlled system-wide or per app, and mixing up the two settings causes most of the confusion.
Change Ringtone
Stuck with the same default ringtone on your Oppo phone and want something else for calls? Coloros lets you pick from built-in tones, but on dual SIM devices each SIM number can carry its own separate sound. Missing this per-SIM setting is why some calls still ring with the wrong tone even after changing it once.
Pair a Bluetooth Device
Turning on Bluetooth on your Oppo phone does not automatically connect it to headphones, speakers, or another phone. Both devices still need to confirm the connection before any file transfer or audio streaming works. If your Oppo phone cannot find the other device or the pairing request never appears, the two devices are simply not linked yet.
Block or Unblock a Contact
If a contact keeps calling or texting you and you want it to stop, blocking them cuts off calls and messages without deleting the contact. On Oppo phones this option sits inside the Contacts app rather than a dedicated blocklist screen, so it is easy to overlook. Unblocking later restores calls and texts from that number right away.
Turn On TalkBack (Accessibility)
If a single tap on your Oppo now selects text and reads it aloud instead of opening the app, TalkBack is likely running. This screen reader changes how taps, swipes, and double-taps work across the whole system. Turning it on or off correctly keeps accidental activation from locking you out of normal navigation.
Turn Power Saving Mode On or Off
If your Oppo phone suddenly dims the screen, cuts the screen timeout to 15 seconds, and stops apps from syncing in the background, Power saving mode is active. This mode can switch on by itself at low battery or stay on after you enabled it manually, and it often delays notifications and app updates. Switching it off brings back normal brightness and sync behavior right away.
Change Time Zone Manually
If you swap SIM cards or connect to a foreign network, your Oppo phone often jumps to the wrong time zone on its own. Clock apps, alarms and message timestamps can then be off by hours, because Coloros pulls the zone from the current network instead of your actual location.