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Samsung

Guides for Samsung Galaxy M21

520 guides

Photo, Video & Media2

Change Album Cover Image

Samsung Gallery replaces an album thumbnail with the newest photo or video every time you add something to that album, so the cover you actually want to see keeps changing. This makes albums with frequent uploads, like a shared family folder or a screenshot dump, hard to recognize at a glance. Locking in one specific cover image fixes that, but the option is buried a few taps deep in the album menu.

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Photo, Video & Media2

Turn Camera Flash On or Off

Photos taken indoors or in low light often turn out dark or grainy because the flash stays in automatic mode and only fires when the camera decides it is needed. If you want the flash to fire on every shot, or stay off completely for a more natural look, you need to take it out of Auto mode. This also affects how the flash behaves while recording video.

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Security & Privacy2

Delete a Saved Fingerprint

Old fingerprints stored on your Samsung phone stay active even after you stop using them, and every extra entry gives a spoofed or borrowed print another chance to unlock the device. If a family member's finger, a child's print, or an unreliable scan is still registered under Fingerprints, it can grant access you no longer want. Removing entries you do not need closes that gap without touching your other saved biometrics.

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Calls & Messages2

Edit a Saved Contact's Details

A contact's phone number or email often changes, but deleting the whole entry and creating a new one throws away the call history and message threads tied to that contact. Samsung's Contacts app lets you update individual fields directly, without breaking the link to existing calls and chats. Skipping this and adding a duplicate contact instead is the most common mistake here.

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Notifications & Focus2

Set Exceptions for Do Not Disturb Sounds and Alarms

When Do Not Disturb mutes your Samsung phone, calls, messages and reminders get silenced along with everything else, even if one of them is urgent. Alarms and media playback stay audible by default, but other sounds stay blocked until you change the settings yourself. This causes missed calls or reminders for anyone who keeps focus mode on for long stretches.

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Apps & Installation2

Add New Apps to the Home Screen Automatically

After installing a new app, you check your Home screen and find nothing there. The app only shows up in the App Overview, which means an extra step every time you want to use it. This happens because the automatic Home screen placement option is turned off by default on Samsung devices.

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Other2

Turn the Flashlight On or Off

Looking for a flashlight app on your Samsung phone? You will not find one, because Samsung built the torch function directly into the quick settings panel instead of a separate app. If you cannot locate the toggle, the tile has usually been moved or removed from your quick settings.

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Display & Home Screen

Turn Night Mode On or Off

If your screen feels too bright in dark rooms or your OLED display drains battery faster at night, Night mode on your Samsung phone is likely turned off. It switches the interface to a darker theme, easing eye strain and cutting power use on OLED screens. You can enable it manually or let it follow a schedule.

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Photo, Video & Media

Take Photos with a Tap on Screen

Holding your phone at arm's length for a selfie makes the shutter button hard to reach, especially with one hand. Samsung's camera offers a shooting method called Tap screen that turns the whole preview into a trigger area instead of relying on the small button. Without it switched on, you're stuck stretching your thumb across the screen every time.

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Calls & Messages2

Merge Duplicate Contacts

If the same person shows up twice or three times in your contact list, an import from SIM, cloud, or a second account has likely created copies instead of updating the original entry. Calls, messages, and search results then jump between the duplicate versions, so you never know which one holds the current number. Samsung's Contacts app can combine these entries automatically once you point it at the matching fields.

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Accessibility2

Schedule Eye Comfort Shield (Blue Light Filter)

Manually turning Eye comfort shield on and off every evening gets old fast, especially when sunset times shift throughout the year. If the blue light filter only ever runs when you remember to tap it, you are missing the automatic scheduling option built into the display settings. A fixed start and end time or a sunset-to-sunrise rule keeps the warm tint active exactly when you need it.

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System & Settings2

Turn USB Debugging On or Off

If a PC tool, ADB command, or rooting software cannot detect the Samsung phone, USB debugging is often disabled or missing from the visible settings. This mode is hidden inside Developer options and stays off by default to protect the device from unauthorized data access. Without it enabled, sync tools and flashing software cannot talk to the system properly.

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Notifications & Focus2

Set a Custom Ringtone

Tired of the same handful of default tones on your Samsung phone? If a downloaded ringtone or your favorite song does not show up when you try to assign it, the sound picker usually just has not scanned that folder yet or the file sits in a format the phone does not recognize as a ringtone.

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Photo, Video & Media2

Empty the Gallery Recycle Bin

Deleted photos and videos in the Samsung Gallery app do not disappear right away. They sit in the Trash for a set number of days before Samsung removes them automatically, and until then they still take up storage space. If you need to free up space immediately or make sure sensitive files are gone for good, you have to clear the Trash yourself.

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Accessibility2

One-Handed Mode Toggle

If your Samsung phone feels too big to use with one hand, reaching the top corners of the screen means constantly shifting your grip. One-handed mode shrinks the display into a smaller window you can move to either side. Without it turned on, you are stuck using both hands for anything above the lower part of the screen.

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Display & Home Screen2

Change Always On Display Orientation

On Samsung phones, the Always On Display defaults to portrait orientation even when the phone sits flat in a stand, car mount, or dock turned sideways. That leaves the clock and icons rotated on their side instead of readable across the screen. The fix sits in a setting most people never open because it is separate from the normal screen rotation toggle.

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System & Settings

Quick Settings Button Grid Size

If your Samsung quick settings panel feels cramped or only shows a handful of toggles, the button grid is likely still stuck on the default size. Switching to a larger 5x3 layout fits up to 15 shortcuts at once, while 3x3 keeps each tile bigger and easier to tap.

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Network & Connectivity2

Set Up a VPN Connection

Streaming services blocking your location, unsecured public Wi-Fi, or a company network that only accepts encrypted traffic - all of these push you toward a VPN. On Samsung phones the connection only routes through a VPN server once a valid profile has been created manually, since One UI does not ship with preset providers.

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Network & Connectivity2

Turn Mobile Hotspot On or Off

If you need to share your Samsung phone's mobile data connection with a laptop, tablet, or another phone, Mobile Hotspot has to be switched on first. Without it, nearby devices cannot detect your phone as a Wi-Fi access point at all. Many people also struggle to find where this toggle sits once they need to turn it off again to save data or battery.

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Notifications & Focus2

Mute a Conversation in Messages

When one contact keeps sending message after message, your phone keeps lighting up and buzzing even though you have no interest in leaving that chat entirely. Samsung Messages lets you silence a single conversation without blocking the sender or deleting the thread. The notification setting for that one chat works independently from your general Messages notifications, so muting a contact won't affect alerts from anyone else.

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Other2

Delete Cookies and Site Data in Samsung Internet

If Samsung Internet keeps showing you the same ads or logs you out of sites you visit often, stored cookies are usually behind it. Site data builds up quietly in the background and can slow down page loading over time. Clearing it wipes the tracking history without touching your saved passwords or bookmarks.

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Calls & Messages2

Rename Contact Group

If a contact group on your Samsung phone still shows the wrong name, the fix only applies to groups you created yourself. Default groups like Family, Colleagues or Friends cannot be renamed, which often confuses users trying to clean up their address book.

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Other2

Turn Data Saver On or Off

If apps stop syncing or notifications only show up after you open them, Data saver is probably cutting their background connection. This mode blocks mobile data for apps running in the background, which can delay messages, emails and updates until you check the app manually. Some apps can still be allowed to use data in the background even while data saving stays active.

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Display & Home Screen2

Set Up Screen Saver

If your Samsung screen saver never appears while charging, or the wrong image type keeps loading, the Screen saver settings usually need a second look. One UI lets you pick between a color change, a photo frame, a single photo, or a photo table, but the toggle for turning the feature on or off sits a few taps deep in Display settings. Getting the wrong option selected often means the screen saver either never triggers or shows content you did not choose.

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