Setting an SD card as the default storage on an Android device allows you to save apps, photos, and other files directly to it, freeing up internal storage. Here’s how you can do it:

Method 1: Format SD Card as Internal Storage (Adoptable Storage)

This method allows the SD card to act as an extension of internal storage.

1. Insert the SD Card into your phone.
2. Go to: Settings > Storage.
3. Tap on your SD Card and then click on the three-dot menu (⋮) in the top-right corner.
4. Select Format as Internal or Use as Internal Storage.
5. Confirm by tapping Erase & Format (this will delete all data on the SD card).
6. After formatting, choose Move Data Now to transfer apps and files to the SD card.
7. Restart your phone.

Note: Some manufacturers disable this feature. If you don’t see the option, your phone may not support adoptable storage.

Method 2: Set SD Card as Default for Photos & Videos

1. Open Camera App > Settings.

2.Look for Storage Location and select SD Card.
3. Now, all captured photos and videos will be saved to the SD card.

Method 3: Move Apps to SD Card (If Supported)

1. Go to: Settings > Apps.
2. Select the app you want to move.
3. Tap Storage > Change > SD Card.
4. Tap Move and wait for the process to complete.

Note: Some apps, especially system apps, cannot be moved to an SD card.

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In conclusion, setting an SD card as the default storage on Android can help free up internal storage and improve device performance. The process varies depending on your phone model and Android version, but the main methods include:

• Formatting the SD card as internal storage (if supported) to use it like built-in memory.
• Setting the SD card as the default location for downloads, camera photos, and media apps.
• Moving apps to the SD card (if allowed by the device).
• Using third-party apps to manage and automate storage settings.

If your device does not have a built-in option to set the SD card as default storage, manually moving files or using third-party tools can still help optimize space.