The main parameters when choosing a memory card are its standard and speed. And suitable ones can be determined from the technical characteristics of the smartphone and the planned operating conditions.


  1. How to choose a memory card for a smartphone: what to look for
  2. Main selection criteria
  3. Additional functions of memory cards
  4. The best memory card manufacturers

How to choose a memory card for a smartphone

How to choose a memory card for a smartphone: what to look for

The most important options for choosing a memory card for a smartphone are as follows:

  1. Standard (defines compatibility and volume limit);
  2. Volume (defines the amount of information that can be written to this drive);
  3. Speed ​​(determines the practicality of the drive for various purposes).
  4. The manufacturer of the device is also important.

It’s worth mentioning right away that the article describes microSD memory cards, since it is it that is used in the vast majority of modern smartphones. Rare models that are equipped with a slot for other types of drives (for example, MMC) are found once in never, and therefore the choice for them is limited simply by finding the right accessory.

Main selection criteria

Criterias of choice

Almost all modern smartphones use microSD memory cards, which are highly practical and compact in size. These external drives are classified as follows:

  1. By standard (microSDSC, microSDHC, microSDXC);
  2. By volume (measured in “marketing” GB);
  3. By speed class (Class 2-10, UHS I-II).

All these parameters are very important when choosing a memory card for use in a smartphone.


There are three standards for microSD memory cards:

  1. microSDSC (Standard Capacity);
  2. microSDHC (High Capacity);
  3. microSDXC (Extended Capacity).

MicroSDSC (may also be called simply microSD) is one of the first memory card standards. It was introduced in the last century. The maximum capacity of such memory cards is 2 GB, and they are formatted in a slow and not very practical type of FAT16 file system.

Memory cards of this standard are currently practically not found on sale. They are recommended for use only with the oldest smartphones.

microSDHC – the most common memory card standard at the moment, providing the best price-volume ratio for mobile users. The capacity of such drives is from 4 to 32 GB, and the most optimal file system is FAT32, which has a high speed of access to recorded information.

MicroSDHC memory cards are recommended for use in smartphones.

MicroSDXC – the most modern standard for memory cards. The capacity of such drives ranges from 64 GB to theoretically 2 TB (with the maximum presented at the moment is 200 GB). They are formatted with the fastest exFAT file system.

The use of such memory cards is recommended in modern flagship smartphones.

Memory card standards are backward compatible. That is:

  1. A smartphone that supports microSDXC memory cards can install microSDXC, microSDHC, and microSDSC;
  2. A smartphone that supports microSDHC memory cards can install microSDHC and microSDSC. But microSDXC will no longer be compatible with it;
  3. Only microSDSC can be installed in a smartphone that supports microSDSC memory cards. The rest will be incompatible.

You can find out what type of memory cards are supported by your smartphone from the technical specifications of the device. Usually the standard is specified directly. If a specific name is not given, then it can be determined indirectly, based on the maximum amount of supported memory cards:

  1. 64 GB or more – microSDXC, as well as all older standards;
  2. 2 GB to 32 GB – microSDHC and microSDSC;
  3. 2 GB or less – microSDSC only.

Almost all modern budget and mid-range smartphones support microSDHC, but the “upper-middle” and flagship ones support microSDXC.

Since the file system of a memory card indirectly determines the speed of access to information, it is also worth choosing a standard based on the planned use. For storing multimedia data, documents, etc. HC is fine, but for installing applications or using it as Adaptive Storage (a feature available in Android 6.0 and 7.0), it is better to use XC.

However, the speed of access to files directly affects the speed of the memory card.

The memory card standard is most often indicated in the description, on the packaging or directly on the case of this drive with the corresponding icon.

Memory card speed class

Speed ​​class

There are several memory card speed classes, and they come in two generations.

The first generation is the “classic” Speed ​​Class. The four most common types are:

  1. Class 2. Read and write speed – from 2 Mbps. Only suitable for documents, small images in poor quality, music with low bitrate, etc. They cannot be comfortably used with modern smartphones – for example, when photographing, the delay in recording a picture will be several seconds, as a result, glitches or defects in the “picture” may appear;
  2. Class 4. Read and write speed – from 4 Mbps. Suitable for music with an average bitrate, low-resolution images, documents and files that you do not need to work with “online” (documents, archives, etc.). Not suitable for video. Not suitable for photography;
  3. Class 6. Read and write speed – from 6 Mbps. Suitable for high bitrate music, medium resolution images (up to 13 MP), other files. Can be used to store and play videos. Limitedly suitable for photography (up to 13 MP, no RAW, no HDR), not suitable for video shooting;
  4. Class 10. Read and write speed – from 10 Mbps. Suitable for almost all purposes, including application installations, still photography (except RAW), video shooting (up to HD).

As you know, Class 6 and Class 10 memory cards will be the best solution for use with modern smartphones. But if you plan to record high-resolution video (Full HD, 4K) or “large” photos (RAW, HDR +) on this drive, then you should pay attention to even faster standards:

  1. UHS-I. Reading and writing speed – from 10 Mbps. Suitable for high-definition video (Full HD), high-bitrate audio (Loseless, ALAC), storage of large files (movies, for example);
  2. UHS III. Reading and writing speed – from 30 Mbps. Suitable for ultra high definition video (QHD, 4K) and any purpose.

It is worth considering that most memory cards with a UHS speed class are made in the microSDXC standard (which is quite logical), so before purchasing such a drive, you should make sure that the smartphone will support it.

Memory card capacity

The amount of data that can be written to it directly depends on the size of the memory card. At the same time, the capacity in GB, which is indicated on the packaging, does not correspond to the real one.

The following sizes of memory cards are most common:

  1. 2 GB (actual 1.9 GB). About a hundred songs in MP3 format 320 kbps or about 200 photos in 8 MP resolution will “fit”;
  2. 4 GB (actual volume 3.72 GB). In addition to the above, a few more videos in 320p will fit;
  3. 8 GB (actual 7.44 GB). Enough for a couple of films in low quality, several hundred files of music, documents and photos;
  4. 16 GB (actual 14.9 GB). Enough for several videos in high definition HD or even Full HD, as well as all of the above;
  5. 32 GB (actual 29.8 GB). Enough for a lot of Full HD videos and lots of high-resolution photos;
  6. 64 GB (actual 59.6 GB). Enough for the average number of videos in QHD or 4K;
  7. 128 GB (actual 119.2 GB). Enough for a lot of clips in 4K or even at 120 fps.

As you know, it is worth choosing the required storage volume based on the planned use. For photographers, memory cards of 32-64 GB are suitable, mobile operators (especially in combination with a modern smartphone) need an accessory of 64-128 GB.

Additional functions of memory cards

Some memory card models offer advanced functionality that can be very useful to users. Among these possibilities:

  1. Data recovery software included. A nice and useful “bonus” that will save your favorite photos, even if something happens to the memory card;
  2. Protection against extreme conditions (too high or low temperatures, shaking, contact with water, etc.). The function is quite useful, but only if you plan to travel a lot with the card;
  3. X-ray protection. Will keep the memory card “alive” after scanning luggage at the airport. Another useful feature for those who like to travel;
  4. Water protection. Such memory cards can dive to a shallow depth for a short time. Another way to save your favorite photos in extreme conditions.

Most often, all these additional features “go” all together. For example, Kingston Industrial Temperature memory cards are protected from cold, heat, x-rays, moisture, even power surges when inserted into or removed from a working smartphone.

The best memory card manufacturers

Among the manufacturers of memory cards, the following companies can be distinguished:

  1. Samsung. Produces memory cards specially optimized for smartphones;
  2. Transcend. Inexpensive, but at the same time, high-quality memory cards;
  3. SanDisk. It produces both relatively inexpensive and premium models.
  4. In addition, Kingston and Silicon Power are worthy of mention, which also produce high-quality and, in most cases, budget memory cards.

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