Transferring data between Android smartphones via a memory card

Changing a smartphone is always stressful, associated not so much with buying a new gadget, but with the fear of losing important information. While cloud services require a stable internet connection and can take hours to sync, physical media remains the most reliable and fastest migration method. Using a memory card microSD allows you to transfer gigabytes of photos, documents and media files in a matter of minutes, without using up mobile traffic.

This method is especially relevant when moving between devices from different manufacturers, where proprietary utilities may not work correctly or require complex configuration. Local copying guarantees that your files will remain under full control and will not be compressed by cloud storage algorithms. In this article, we will analyze in detail the process of preparing the media, the folder structure and the nuances of transferring system data.

Preparing a memory card and checking compatibility

The first step is to assess the capabilities of your drive. Not every card is suitable for quickly transmitting a large amount of information. If you plan to transfer 4K video or heavy game archives, make sure yours meets the standard microSD meets the standard Class 10 or higher and is labeled UHS-I or UHS-II. Slow Class 4 or 6 cards will become a bottleneck, turning the copying process into an hours-long wait.

It is also important to check the physical compatibility of the slots. Modern flagships are increasingly abandoning hybrid trays, leaving space only for SIM cards. If your new device does not have a memory card slot, you will need an external card reader with USB OTGsupport. In this case, the card is inserted into the adapter, which connects directly to the port USB Type-C of the smartphone.

⚠️ Attention: Before starting work, be sure to remove the memory card from the old phone through the menu Settings → Storage → Remove SD card. Abruptly physically removing a working drive can lead to damage to the file system and loss of some data.

Make sure that the file system of the card is understandable to both devices. The de facto standard for Android is exFATwhich supports files larger than 4 GB. If your card is formatted in legacy FAT32, you won't be able to copy large video files or disk images to it without first partitioning it.

Step-by-step guide for copying files from an old device

The process of transferring data begins with organizing the folder structure on the media. Chaotically copying files to the root directory will make them difficult to find on a new device. It is recommended to create a directory in advance with a clear name, for example, Transfer_2026, and within it distribute the content by type.

Open the file manager on your old smartphone and select the necessary data. For photos and videos, the standard paths are folders DCIM/Camera and Pictures. Documents are often stored in a directory Download or in specific application folders such as WhatsApp/Media. Select the desired elements with a long press and select the function Copy or Move.

• 📁 Photo and Video: Folders DCIM, Pictures, Movies, Camera.
• 📄 Documents: Folders Download, Documents, as well as files in the root of the storage.
• 🎵 Audio: Folders Music, Ringtones, Notifications, Audiobooks.
• 📦 Archives and APK: Any downloaded application installers or ZIP archives.

After selecting the files, click the insert button into the target folder on the memory card. The recording speed will depend on the number of small files: copying thousands of small photos takes longer than transferring one movie weighing several gigabytes due to the peculiarities of the memory controller.

Transferring contacts and messages via export

The most difficult moment when using a memory card is transferring not files, but system records, such as contacts and SMS. The Android file system does not allow you to simply copy the contacts database, since it is encrypted and tied to a specific OS instance. However, there is a universal way to solve this problem by exporting to standard formats.

To transfer the phone book, open the application Contact. In the settings menu (usually three dots or a gear icon), find the item Import/Export contacts. Select option Export to storage or Export to file .vcf. The system will create a file, usually called contacts.vcf or 00001.vcf, which will be saved to internal memory or directly to an SD card.

⚠️ Attention: Format .vcf saves only contact text (name, number, email, address). Photos linked to contacts and call history are not saved during this export. For a complete backup of call history, you will need third-party applications.

You can do the same with messages, although this is done less frequently using standard Android tools. There are applications that allow you to export SMS to XML or JSONformat, which can then be saved to a card and restored on a new device using the same application. This is the only way to save correspondence without using Google cloud backups.

What to do if exporting contacts is not visible on the map?

Sometimes the file is saved to a hidden system folder. Try turning on the display of hidden files in the file manager settings, or when exporting manually, select the save path to a visible directory, for example, the Download folder.

Migrating data to a new smartphone

After successfully copying all the data, remove the card from the old device and install it in the new smartphone. If your new phone immediately prompts you to format the card as internal storage, refuse this if you want to maintain the ability to read data on other devices. Select the operating mode as Portable storage.

Now open the file manager on the new device and go to the contents of the SD card. Find the data folder you created earlier. To restore contacts, just click on the file .vcf. The Android system will automatically recognize the format and offer to import the found entries into the phone book or Google account.

When importing contacts, the system may ask where exactly to save the data: to the phone memory, to the SIM card or to the account. It is recommended to select Google Account or phone memory, as this will provide better synchronization and display of additional fields that are not supported by the legacy SIM storage format.

Data Type	Transfer Method	File format	Nuances
Photo and Video	Copying folders	JPG, PNG, MP4, MOV	Original quality and EXIF data are maintained
Contact	Export/Import	.vcf (vCard)	Does not transfer photos of contacts and call history
Documents	Copying files	PDF, DOCX, XLSX	Requires installation of appropriate viewing applications
Music	Copying folders	MP3, FLAC, WAV	You may need to scan your media library again

Working with application data and settings

Transferring installed applications via a memory card is not a trivial task. In modern versions of Android, direct installation of applications (APKs) from external storage devices is limited for security reasons. You can copy the installation files .apk to the card, but when you try to install, the system may block the process if the source is not verified.

To legally install applications from a memory card, you will need to allow installation from unknown sources for your file manager. Go to Settings → Applications → Special access → Install unknown applications and activate the permission for the selected explorer. After this, launching the APK file from the card will launch the standard installation wizard.

However, it is worth understanding that only the applications themselves are transferred in this way, but not their data (logins, game progress, settings). Application data is stored in a protected section of internal memory /data/data/, access to which without superuser rights (Root) is prohibited. Therefore, games and apps will have to be set up again or logged into your accounts.

⚠️ Attention: Settings menu interfaces may vary depending on the version of Android and the manufacturer's shell (MIUI, OneUI, ColorOS). Menu items may have different names, but the logic for working with access rights remains the same.

Possible problems and solutions

During the migration process, users often encounter the “File is too large” error when trying to copy a video to a memory card. This is a classic file system problem, which has a 4 GB limit on the size of a single file. The solution is to format the card in exFAT format, but this will delete all data on it, so this procedure must be carried out before copying. FAT32, which has a single file size limit of 4 GB. The solution is to format the card in exFAT format, but this will delete all data on it, so this procedure must be carried out before copying.

Another common problem is the invisibility of files on the new device. This may occur if the Android media scanner has not yet updated the database. In this case, it is recommended to restart your smartphone or use an application to clear the media storage cache. Sometimes simply waiting for 10-15 minutes after inserting the card helps.

If a memory card is not at hand, and the slots in the phones do not match, you can use the drive emulation mode. Connect your old phone to your computer, copy the data to the PC, and then from the PC to the new phone. Although this requires an intermediate link, the principle remains the same - physically copying the file structure.

Why are photos not displayed in the gallery after transfer?

The Android gallery works based on a database of media files. After transferring a large amount of data, the system may not immediately scan the new card. Try clearing the cache of the "Media Container" application in the application settings.

Is it possible to transfer applications along with saves via a memory card?

Without root access, it is impossible to transfer the application data itself (saves, logins) using standard means. You can only transfer the APK installation files, but the app will be clean when installed. To completely clone applications, it is better to use the “Restore from Google Backup” function when setting up your phone for the first time or specialized software like Swift Backup (requires Root).

What to do if the new phone does not see the memory card?

Check whether the card is inserted correctly (contacts down). Make sure the card is formatted with a compatible file system (exFAT or FAT32). If the card was used as “internal memory” on the old phone and was encrypted, the new phone will not be able to read it without formatting, which will delete all data.

Is it safe to store personal data on a memory card?

The memory card does not have hardware encryption by default, like the internal memory of modern smartphones. If you lose the card, anyone can read its contents by connecting it to a computer. To protect sensitive data, it is recommended to use encrypted archives (ZIP with a password) or the “Secure Folder” function, if available on your device.

What speed of memory card should you choose for quick transfer?

For comfortable work and quick copying, choose cards with markings U3 i V30. This guarantees a recording speed of at least 30 MB/s, which is critical when transferring high-definition video. Class A1 or A2 cards are also preferable if you plan to run applications directly from the card.

Do you need to format the card after transferring data?

No, formatting is not required if you plan to use the card in a new phone to store files. However, if you used the card as a temporary buffer and want to return it to your old phone or use it in your camera, formatting can be useful to clear temporary files and correct possible file system errors.