What is partitioning an SD card for internal storage?
Partitioning an SD card for internal storage allows you to expand the internal storage capacity of your Android device. This is done by formatting and dedicating an SD card to act as an extension of the built-in internal storage.
When you adopt an SD card as internal storage, the card is encrypted and formatted to only work with that specific device. The SD card essentially becomes part of the phone’s internal storage.1 This allows you to:
- Install more apps since you have more storage space.
- Save more photos, videos, and files on your device.
- Improve app performance by running apps from the faster SD card.
Overall, adopting an SD card lets you dramatically expand your Android’s usable storage, which is useful if you have a device with limited built-in storage.
Requirements for partitioning an SD card
To use adoptable storage, your Android device must meet certain requirements related to the Android version and the capabilities of the SD card.
For Android version, adoptable storage is supported on Android 6.0 Marshmallow and higher. Older versions of Android do not have this feature. So you need to be running at least Android 6.0 on your device [1].
In terms of the SD card, there are some specific requirements [2]:
- The SD card needs to have a capacity of at least 32GB.
- The speed class rating needs to be UHS-I or higher for optimal performance.
- Lower speed SD cards can still work, but may result in slower performance.
Meeting these Android version and SD card requirements will allow you to use adoptable storage to effectively expand the internal storage of your device.
How to partition an SD card
Partitioning or formatting your SD card as internal storage allows you to expand the available storage on your Android device. Here are the key steps to format an SD card as internal storage on Android:
1. Insert the SD card – Remove any protective case and insert your SD card into the phone’s SD card slot.
2. Open Settings – Open your Android device’s Settings app.
3. Select Storage settings – Go to the Storage or Storage & USB section in Settings.
4. Choose your SD card – Select your external SD card from the list.
5. Tap Format as internal storage – You may need to tap the 3-dot menu and select Storage settings first.
6. Confirm formatting – Read the warning prompt carefully and confirm you want to format.
Formatting as internal storage means the card can be read much faster than portable storage. However, you cannot remove the card without reformatting. Portable storage lets you freely insert and remove the card.
Adoptable storage integrates the SD card into the internal storage by formatting and encrypting it. This allows your apps and data to seamlessly extend onto the card. Portable storage keeps the SD card separate as removable media.
Moving apps to the SD card
One of the main benefits of adopting your SD card as internal storage is being able to move apps from your phone’s internal storage over to the SD card. This frees up precious space on your phone’s internal storage.
There are two main ways to move apps to your adopted SD card storage:
Set default installation location to SD card
Once you have adopted your SD card, you can set your phone to automatically install new apps to the SD card rather than internal storage. To do this on a Samsung device running Android 10 or later:
- Go to Settings > Apps.
- Tap the three dot menu in the top right corner and select “Default apps.”
- Under “Install new apps to,” select your SD card.
Now any apps you download from the Play Store will be installed to the SD card by default [1].
Manually move apps
You can also manually move already installed apps from internal storage over to the SD card:
- Go to Settings > Apps.
- Tap the app you want to move.
- Tap Storage.
- Tap the Change button to move the app to the SD card.
This will move both the app itself and its data over to the adopted SD card storage. Keep in mind some apps do not support being moved to external storage.
Using the SD Card Storage
Once your SD card is set up for adopted storage, you can start managing content on it. Here are some tips for optimal performance:
Move large apps and games to the SD card to free up internal storage space. Go to Settings > Apps & notifications > App info, select the app, and tap Storage. Then tap CHANGE and select the SD card.
For best performance, move apps you don’t use frequently to the SD card. Apps stored internally will launch faster. Only move large, infrequently used apps to the SD card.
To move photos, videos, and other media to the SD card, go to Settings > Storage and tap the SD card name. Then tap Migrate data and select the content to move.
Check that you’re using a high-speed SD card. UHS-1 and UHS-3 cards offer the fastest performance. A card with lower read/write speeds can cause lag.
Disable apps you’re not using to optimize performance. Freeze or force stop unused apps in Settings.
Keep at least 500MB of free space on the SD card for optimal speed.
Consider using an SD card optimization app like SD Booster to configure cache settings and clear junk files.
Back up your SD card data periodically in case of corruption. Apps like Migrate can schedule backups.
Test SD card read/write speeds with an app like SD Test. Replace cards under 10MB/s.
Encrypting the SD Card
Encrypting your adopted SD card storage provides important security benefits. When you adopt your SD card as internal storage, the Android system automatically enables encryption for the card using your device’s lock screen password (source: https://source.android.com/docs/core/storage/adoptable). This protects your sensitive data in case your phone is lost or stolen.
Encryption scrambles the data on the SD card so that it can only be accessed if the correct password is entered. This prevents others from accessing your files and information on the card if they remove it from your phone (source: https://www.reddit.com/r/AndroidQuestions/comments/p0acmu/differences_between_sdcard_encryption_vs/). The encryption keys are securely stored on your device’s internal storage.
When you adopt an SD card, all the data will be fully encrypted. There are no additional steps needed to enable encryption. The Android system handles it automatically. Adoptable storage requires metadata encryption by default whenever file-based encryption (FBE) is enabled on your device (source: https://source.android.com/docs/security/features/encryption/metadata).
In summary, adopting your SD card as internal storage provides the key benefit of automatic full disk encryption, securing your data and preventing unauthorized access. The Android OS transparently manages the encryption keys and processes.
Troubleshooting Issues
Adopted storage can sometimes encounter problems that prevent it from working properly. Here are some tips for troubleshooting common issues:
If adopted storage suddenly stops working, try rebooting your device. In some cases, a simple reboot can fix problems with the SD card being detected. If that doesn’t work, go to Settings > Storage and tap on your SD card. Then select “Migrate data” to move content back to the phone storage and reformat the card. Afterwards, set it up again as adopted storage.
If apps start freezing or crashing when run from the SD card, go to Settings > Apps and try moving the problematic apps back to the phone storage. There may be compatibility issues with some apps on adopted storage.
In rare cases, the SD card itself may become corrupted. If you notice severe performance issues or errors related to adopted storage, try removing the card and scanning it for errors on a PC. You may need to reformat the card before re-inserting. Be aware this will erase all data.
As a precaution, make sure you have backups of important data on the SD card. If troubleshooting does not resolve the adopted storage issues, a full reformat may be necessary [1].
Backing up data
When using adopted storage, it’s important to regularly back up the data on your SD card. There are a couple options for backing up the data:
You can connect your phone to your computer and use Android’s USB mass storage mode to access the SD card and copy files off of it. This will allow you to back up photos, videos, and any other files stored on the adopted storage.
Another option is to use a dedicated backup app like MyBackup Pro which can back up app data, WiFi passwords, and more to the cloud or your computer. This will help preserve your apps and settings.
To migrate your data to a new, larger SD card, you’ll first need to back up the contents of your original card using one of the methods mentioned above. Then, insert the new SD card into your phone and format it as adopted storage. Finally, restore your apps and data from the backup.
Regularly backing up adopted storage is crucial to avoid losing your files and information if your SD card becomes corrupted or damaged. Be sure to back up important photos, videos, and app data on a routine basis.
Removing or reformatting the SD card
Before removing or reformatting an adopted SD card, it’s important to properly eject it first to avoid data loss or corruption. Here are the steps to safely eject the SD card:
- Go to Settings > Storage.
- Tap on your SD card name.
- Tap on the 3-dot menu in the top right corner.
- Select “Eject”.
This will safely disconnect your SD card so it can be removed without issues. Once ejected, you can physically remove your SD card from your device.
To revert your adopted SD card back to portable storage:
- Go to Settings > Storage.
- Tap on your SD card name.
- Tap on the 3-dot menu in the top right corner.
- Select “Format as portable”.
- Confirm to format the SD card.
This will reformat your SD card as regular removable storage. All data on the card will be erased in the process. After reformatting, you can use the SD card as portable storage again.
It’s recommended to back up any important data before reformatting. Once reformatted as portable storage, you can freely insert and remove the SD card without needing to eject it each time. But be sure to unmount it first whenever possible to prevent data loss.
Alternatives to adopted storage
There are a few alternatives to using adopted storage if you don’t want to reformat your SD card:
Using portable SD card storage
You can use your SD card as portable storage instead of adopted storage. This means the card acts like traditional removable storage – you can freely insert and remove it. Data stored on the card isn’t encrypted and apps can’t be installed to the card in this mode. Portable storage allows you to manually move files, photos, videos etc. to free up internal storage. A downside is you have to manually manage where data is stored.
To use your SD card as portable storage, simply insert the card and do not format it as internal storage. You can then copy files or media to the card using your device’s file manager.
Cloud storage options
Services like Google Drive, Dropbox, Microsoft OneDrive and iCloud provide cloud storage that can supplement limited internal storage. The benefit of cloud storage is it’s accessible from all your devices and you don’t have to manage physical media. However you need an internet connection to access cloud storage.
Most cloud services have free tiers with 15-20GB of storage, with paid plans available for more storage. You can automatically sync photos, videos, documents etc. to cloud storage using apps provided by cloud storage providers.