Smartphone users often face a critical lack of free space in the internal memory of the device. This problem is especially acute on devices with 16 or 32 gigabytes of built-in storage, where the operating system and basic apps occupy a significant part of the volume. Android 9 Pie brought a number of changes to memory management, but many manufacturers still limit the ability to fully use external drives. Understanding how the file system works in this version of the OS is the key to freeing up those precious gigabytes.
Unlike earlier versions, the standard application transfer through the settings menu is often grayed out or only available for select apps. This is due to Google's security policies and the whims of shell manufacturers such as MIUI, OneUI or EMUI. However, there are proven methods to overcome these limitations and turn the memory card into a full-fledged extension of the internal storage. We will look at both standard settings and advanced methods using USB debugging.
⚠️ Attention! Before starting any manipulations with the memory card, be sure to create a backup copy of all important data (photos, videos, documents) on your computer or in cloud storage. The process of formatting a card for use as internal storage will completely erase all information on it.
Checking compatibility and preparing the drive
The first step before attempting to transfer data is to evaluate the capabilities of your specific device. Not all smartphones running Android 9 support the Adoptable Storage function, which allows the system to perceive the SD card as part of the internal drive. You need to make sure that the memory card slot is physically intact and the device recognizes the drive correctly. The speed of the card directly affects the performance of the system, so saving on the speed class can lead to interface slowdowns.
It is recommended to use memory cards of class UHS-I U3 or higher, since applications installed on slow drives will take longer to launch. Insert the card into the slot and wait for the system notification. If your smartphone prompts you to select a storage mode, this is a good sign. Otherwise, you will have to look for hidden settings or use your computer to force the feature to activate. You can check the current status in the storage information section.
- 📱 Make sure that the memory card has a capacity of at least 16 GB, although for comfortable work it is better to use 32 GB or 64 GB.
- ⚡ Check the card markings: look for the V30, U3 or A1/A2 icons, which guarantee high random read speed and recordings.
- 🔒 Remove the card through the settings menu before physical installation, if it has already been inserted, to avoid file system errors.
Standard method through system settings
The easiest and safest way to change the installation location of applications is to use the built-in tools of the operating system. This method does not require connecting to a computer or installing additional software, but its availability depends on the generosity of your smartphone manufacturer. If the function is available, the system itself will offer to format the drive as required. You just need to follow the prompts on the screen, carefully reading the warnings about data loss.
Go to the menu Settings → Storage (or Memory). Select your SD card from the list of available drives. If you see a menu button (three dots) or a Storage Settings option, click on it. The option “Use as internal storage” or “Format as internal memory” should be present here. After selecting this option, the system will begin the process of encrypting and formatting the card into a file system ext4 or f2fscompatible with Android.
After formatting is complete, the system can Offer to transfer existing data, including applications and media files, to the new drive. Agree to this offer to free up space immediately. Now, when installing new apps from Google Play the system will select the memory card by default if there is enough space on it. However, remember that some system applications and widgets will still remain on the built-in disk for stability reasons.
☑️ Standard transfer algorithm
⚠️ Attention! Once the card is formatted as internal storage, it will be encrypted with your specific device's key. You will not be able to read data from this card on another smartphone or computer without a complete reset and loss of information.
Activation through the developer menu (for hidden functions)
If the standard menu does not have the option to format the card as internal memory, do not despair. In Android 9, you can often activate this feature through a hidden developer menu. This method works on many devices where the manufacturer has simply hidden the interface button, but has not disabled the feature itself at the kernel level. You will need to enable debugging mode and find a special switch responsible for forcing the use of an external drive.
First, activate developer mode. Go to Settings → About phone and find the item “Build number”. Quickly click on it 7 times in a row until the message “You have become a developer” appears. Now return to the main settings menu, where a new section has appeared System → For developers. Scroll down to the "Applications" or "Network" section and find the "Preferred installation location" or "Force allow apps on external" item.
Change this option to "External storage" or "SD card". After this, reboot your device. Now, when you try to install an application or in the properties of already installed apps, a “Change” or “Move to SD card” button may appear. This method is less reliable than full formatting, since applications are partially moved, but it often helps to win several gigabytes of free space without complex preparation.
What to do if the item does not appear?
If, after enabling the developer mode, the desired item is not displayed, it is possible that the manufacturer of your firmware completely cut this function from the system core. In this case, only using ADB commands through a computer or installing custom firmware will help, which requires more in-depth knowledge.
Advanced method using ADB commands
For users who are ready for a more technical approach, there is a universal way to turn any SD card into internal memory using a computer and utility ADB (Android Debug Bridge). This method bypasses the software limitations of the interface and accesses the Android storage manager directly. It works on most devices with an unlocked bootloader or even without it if USB debugging is enabled. You will need a USB cable, a computer and installed drivers for your smartphone.
Connect your phone to the PC in USB debugging mode. Open a command prompt or terminal on your computer in the folder with the ADB files. Enter the command adb shell to gain access to the device shell. Next, you need to find out the ID of your memory card. Enter the command sm list-disks. The system will respond with a line like disk:179,64, where the numbers may differ. Remember this identifier, it is critical for the next operation.
adb shell sm partition disk:XXX,XX privateReplace XXX,XX with your disk identifier. This command initiates the process of partitioning and formatting the card into private mode, making it part of the internal memory. The process may take several minutes. Once completed, reboot your smartphone. The system will now see the combined amount of memory. If the card is detected, but applications are not transferred, try the command pm set-install-location 2, which forcibly changes the installation priority to external storage.
If the sm partition command gives an error or freezes, try first formatting the card in FAT32 via a computer, and then inserting it into the phone before entering the command. This helps the system correctly recognize the disk.
Moving installed applications manually
Even after setting up the memory card, many already installed applications will not be moved automatically. You will have to do this manually for each app that supports such a feature. Go to Settings → Applications and notifications → Application information. Select the desired app from the list. If the developer has allowed the transfer, you will see an active button Storage, and inside it - a “Change” button.
Click "Change" and select "SD card". The system will begin the process of migrating application data. Transfer time depends on the size of the app and the speed of your card. Please note that system applications and some important Google services (for example Google Pay or keyboards) often do not have this button. This is a security limitation, since their operation is critical to starting the system, and transferring to removable media may lead to instability.
| Application Type | Possibility of transfer | Recommendation |
|---|---|---|
| Games with cache | Partial (APK only) | You can transfer, but the cache may remain inside |
| Social network | Full | Recommended to be transferred to save space |
| System services | Prohibited | Leave only in internal memory |
| Messengers | Depends on the version | It is better to transfer media files manually to the application settings |
It is worth noting that when transferring an application, its shortcut may temporarily disappear from the desktop or the app may restart. This is normal system behavior when changing the path to executable files. If after transferring the application does not work correctly or crashes, return it back to the internal memory using the same settings mechanism. Not all apps are optimized for working with external memory, especially older versions of software.
⚠️ Attention! Do not remove the memory card while the phone is on and there are active applications installed on it. This will lead to immediate closure of apps, loss of unsaved data, and possible corruption of the application database.
Troubleshooting and common errors
During the setup process, users may encounter various errors, from the “Not enough memory” message to the system completely refusing to see the card after formatting. Often the problem lies in the file system: if the card was formatted on exFAT on a computer, Android 9 may not be able to convert it without completely erasing it. There may also be conflicts with access rights if the card was previously used as portable storage with residual files.
If the phone does not see the card after the ADB command, try reconnecting it in the off state. In rare cases, resetting the phone to factory settings (Hard Reset) helps, but this is a last resort. Make sure the card isn't counterfeit: Cheap cards that claim to be 128GB often have a real capacity of 8GB, causing write errors when you try to fill them with data. Use utilities like H2testw on a PC to check the actual volume before using it in a smartphone.
The stability of a smartphone with applications on an SD card directly depends on the quality of the drive itself. Cheap cards can cause system freezes and data loss.
FAQ: Frequently asked questions
Is it possible to transfer WhatsApp and its correspondence to an SD card on Android 9?
Directly transferring the WhatsApp application itself to the card is often impossible due to security restrictions of the messenger. However, you can transfer media files (photos, videos) and chat backups. To do this, in WhatsApp settings, select “Data and storage” and specify the path to save media to the SD card. The database can be moved manually through a file manager by copying the folder WhatsApp/Databases to the card, but automatic recovery from it may not work without root access.
Why do applications run slower after the transfer?
The speed of applications directly depends on the speed of reading random blocks of data. The internal memory of smartphones (even budget ones) is usually faster than cheap memory cards of class 4 or 6. If your card is not marked A1 or A2, it will not physically have time to load application resources, which will lead to slowdown of the interface and long launch of apps.
What will happen if I insert this card to another phone?
If you formatted the card as internal memory (Adoptable Storage), it is encrypted with a device-specific key. In another phone, the system will offer to format it again, which will delete all data. It is impossible to read files or run applications from such a card on another device without complex manipulations with decryption.
How to return everything back to the internal memory?
To do this, go to Settings → Storage, select the SD card and click “Format as portable storage”. The system will warn you about loss of data on the card. After this, you will have to manually transfer the applications back through the Applications menu, since there is no automatic reverse migration of all data at once.