Expanding Memory on Your Smartphone: A Guide to Using Micro SD Cards

As smartphone storage continues to fill up quickly with photos, videos, apps, and more, many users are looking for ways to expand the memory capacity of their devices. One popular option is using a microSD card, also known as a memory card. microSD cards provide additional storage space for your smartphone, allowing you to store substantially more data.

This guide will provide an overview, discussing what they are, how they work, their advantages and disadvantages, what to look for when buying one, how to install and use it, transferring data tips, maintenance recommendations, and more. Follow along to learn everything you need to effectively expand the storage space on your smartphone.

What is a microSD Card?

What is a microSD Card

A microSD card, sometimes referred to as a memory card, is a small, removable flash memory card that is used for storing photos, videos, music, documents, and other files on devices like smartphones, tablets, and cameras.

microSD cards are about the size of a fingernail and weigh just a few grams. They connect to the microSD card slot built into a device. Once inserted, the card acts as additional storage space for the device it is connected to. microSD cards come in different storage capacities, typically ranging from 16GB to 512GB, allowing you to store substantially more data.

MicroSD cards are a type of removable storage device. This means you can take the card out of your device when you want to transfer files to another device, free up storage space on your smartphone, or replace the card with a higher-capacity one.

How Do microSD cards work?

How Do microSD cards work

microSD cards are flash memory cards, meaning they store data electronically rather than magnetically like traditional hard drives. They are non-volatile memory, so they can retain data even when not powered on.

The card is made up of flash memory chips and a controller chip. The flash memory chips store the actual user files, while the controller chip manages the operation of the microSD card, including writing/reading data, memory management, security, power control, and more.

When inserted into a device like a smartphone, the device’s operating system will mount the microSD card as external storage. You can then store and access files on the card just like you would the built-in storage. The smartphone can read and write data to the card as needed.


There are several notable benefits to using a microSD card for extra storage space on your smartphone:

  • Adds substantial storage capacity – microSD cards can add anywhere from 16GB to 512GB+ extra space.
  • Cost-effective – It’s an affordable way to add a lot of storage compared to upgrading your smartphone. Prices range from $10-$100+.
  • Easy to use – they are plug-and-play. Just insert the card and you instantly have more storage.
  • Portable – Cards are tiny and lightweight, making them easy to take with you.
  • Reusable – If you get a new phone, you can remove the card and use it on the new device.
  • Backs up data – Provides an easy way to back up your data.
  • Allows transfer of files – This lets you easily transfer files between devices.


However, there are also some downsides to be aware of with microSD cards:

  • Can be accidentally erased – There is the risk of accidentally deleting files on the card when it is connected to devices.
  • Potential corrupted data – There is a small chance of data on the card becoming corrupted.
  • Slow speed – it generally have slower data transfer speeds than internal storage.
  • Possible compatibility issues – Some older/low-end smartphones don’t support high capacity cards.
  • Extra step to manage storage – You have to actively manage what data goes on the card vs internal storage.
  • Potentially less secure – A removable card could be more susceptible to malware if used with an infected device.
  • Physical damage/loss – The small size makes them easy to lose and prone to damage if not cared for properly.


What to Look for When Buying

What to Look for When Buying

If you’ve decided to purchase a microSD card for extra storage, there are several factors to take into account:

1. Storage Capacity

Consider how much extra space you need. Cards are available in sizes from 16GB up to 512GB and even 1TB. A 32 or 64GB card is sufficient for most users’ needs. Go for a larger 128-512GB card if you store a lot of media.

2 Speed Rating

Faster cards have quicker data transfer speeds for an improved user experience. Look for Class 10, UHS-1, or UHS-3-rated cards for optimal performance in smartphones. These can read/write data at faster speeds.

3. Brand

Stick with major reputable brands like SanDisk, Samsung, Sony, Kingston, etc. They produce quality, durable cards that meet performance standards. Avoid cheap generic cards that could have reliability issues.

When looking for a reliable, high-performance microSD card for your smartphone or any expansion chips and drives you need, consider exploring options from trusted online retailers such as Bulk Memory Card. Bulk Memory Card is an online retailer that specializes in microSD cards, flash drives, SD cards, etc. from all the top brands like SanDisk, Samsung, Sony, and more. They offer a wide selection of storage capacities and speed ratings at competitive prices. Click here to check them out.

microSDHC vs. microSDXC

Check which format your smartphone needs. microSDHC works for 32GB and smaller cards. microSDXC is required for 64GB+. Most phones support SDXC but verify before buying.


Many microSD cards come with manufacturer warranties against defects, usually 1-5 years or more. A longer warranty is ideal for peace of mind.


Cards range widely in price from $10 to $100+. Consider how much storage you need when factoring in price. More storage means a higher price.

How to Install and Use

Installing a microSD card into your smartphone is a quick and simple process:

Locate the slot on your phone – usually on the side or bottom edge. Carefully insert it into the slot with the gold contacts facing down and angled edge first. Push gently until it clicks into place. The phone should automatically detect and mount the card. You may get a notification that new storage is available.

To confirm it is properly installed, go to Settings > Storage on Android or Settings > General > Storage on iPhone to verify your total capacity increased. You can now start storing files like photos, videos, and downloaded apps onto the SD card. Make sure to allow app storage on the card if prompted.

To remove the card, go to Settings and tap on the SD card name, then choose the eject/unmount option. You can then gently pull out the card. Insert it into a new phone and it will remount it automatically so you can access all your stored files.

Tips for Transferring Data to the microSD Card

Transferring Data to the microSD Card

When adding a microSD card to your smartphone, you’ll want to transfer data like photos, videos, and apps over to the new storage space. Here are some tips:

  • Move media files (photos, videos, music) by going into your Gallery/Photos app and using the migration option to transfer the files.
  • Transfer compatible apps over to the card using your phone’s App Manager if prompted. This frees up internal storage.
  • Use your file manager/explorer app to manually move documents, downloads, and other files onto the SD card for organization.
  • Backup important files and folders onto the memory card for safekeeping in case anything happens to your phone.
  • Save all new photos/videos you take directly onto the SD card from the get-go. Change this in your Camera app settings.
  • Adjust your downloads folder to save onto the card to avoid filling up internal storage when downloading files.
  • Check your streaming apps like Spotify to see if you can move the cached/downloaded content onto the card.


To keep your microSD card functioning properly and stored data protected, follow these maintenance tips:

  1. Safely eject the card before removing it from your phone to avoid corruption.
  2. Be gentle when handling the card as the small size makes them prone to damage. Avoid touching the gold contacts.
  3. Keep the card away from liquids, extreme heat, and other environmental hazards.
  4. Back up important data from the card to other locations in case the card becomes corrupted or damaged.
  5. Reformat the card every 6-12 months to refresh the memory sectors and fix any lingering issues.
  6. Replace the card if it becomes noticeably slower or less reliable; they have a finite lifespan.
  7. Check your stored files on the card periodically and delete those you no longer need.
  8. Be aware of fake/counterfeit cards sold online and only buy from reputable retailers.
  9. Update your SD card if you get a new smartphone that requires a different capacity card or format.


Adding removable microSD card storage is an easy and affordable way to expand the memory capacity of your smartphone. When shopping for a microSD card, look for reputable brands, sufficient storage capacity for your needs, optimal speed rating, and reasonable price.

Installation is a simple plug-and-play operation. Maintain your card properly by safely ejecting it, avoiding environmental hazards, reformatting periodically, and replacing it after prolonged use. With a new one installed on your phone, you’ll be able to store substantially more photos, videos, apps, and files.