Many cell phones, including most smartphones, allow you to add extra storage to your phone by inserting an SD card, a micro SD card or a mini SD card. You can store photos or videos on the SD card to easily transfer them to your computer, or you can store music, movies or files for your digital books without taking up valuable space on your phone. Many Android, BlackBerry and Windows phones support SD cards, but as of November 2013, iPhones do not.
Format Your SD Card
Some smartphones accept SD cards formatted by computer, for example Android phones use a FAT32 file format system, which you can set up on your Windows or Linux computer using file formatting software. All smartphones that accept SD cards, like Androids and Blackberrys have a built in application that formats them right from the phone, ensuring that your phone has no difficulty reading the files there. Warning: formatting the SD card means erasing all of the files already on it. Back up your files to your computer first.
Mount the SD Card on Your Computer
Some computers have a built-in SD card slot and you can use adapters for microSD cards or miniSD cards. You can also put the SD card into a USB adapter for a computer that does not have an SD card slot. Follow the phone manufacturer's instructions for removing your SD card to avoid damaging or corrupting files. If you want to mount the SD card on your computer without removing it from your phone, many phones use a USB cord that allows you to mount your entire phone, including the SD card, as a mass storage device or a removable disk.
Launch your file manager and locate your phone's SD card. If you mounted it on its own, it may show as an SD card, but if you mounted your entire phone, it may show as a mass storage device or a removable disk. It is usually easiest to find by the size of the card. Copy and paste the files you want on your phone's SD card, just as you would into any other folder on your computer's hard drive. When you are finished, unmount the SD card, or your phone, before you eject it to keep the files from corrupting.
Where Do the Files Go?
The apps you have installed on your smartphone dictate where certain files go and what can access them. For example, an Android phone stores photos in a folder labeled "DCIM" which is often in the Media folder. Different phones have different ways of accessing files from applications, so if you are moving files for a specific application to use, make sure you follow instructions for that application about where to put them. Some smartphones come with a file browser to allow you to access files placed in the wrong folder and select which app to use to open them, but some do not.
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