The purchase of a new microSD card should not be complicated. Want to expand your smartphone's memory? Take a microSD and place it on a smartphone. But is everything so simple?
SD and microSD cards use an absolute majority of cameras, laptops, photo frames, sound recorders, and so on. But with Android smartphones everything can be more complicated!
The first suggestion - do not buy a microSD or SD memory card on eBay or other online stores. Our friendly Chinese vendors will, at best, send out a 4 GB memory card, which with a few tricks on your computer will appear as a 32 or 64 GB card. After formatting the SD card, you will see the actual, tiny memory if the memory card works at all... At us in Latvia, the microSD card is at very attractive prices, unless you buy a microSD in a supermarket at the cash register.
Different formats - Smartphones use a microSD while cameras use full-size SD cards. Of course, the microSD with an adapter can be converted to an SD card, but in the opposite direction it will not succeed. In the shop, it's important to check if you've really got microSD - prices today are not different for microSD and SD cards. Theoretically there's is also a miniSD sized memory card, but it's unlikely to be so easy to buy.
Before purchasing, find out the maximum amount of microSD memory that your smartphone supports. In modern times, smartphone manufacturers in large numbers will take up to 2 TB memory cards, usually the maximum size will be 256 GB. Older smartphones should look at the manual as they usually support up to 32 GB.
I'm rolling out all the time for "microSD", but actually the names of memory cards are also allocated depending on the amount of memory. The microSD supports up to 2 GB (in some cases also 4 GB), 4 to 32 GB is called microSDHC (Secure Digital High Capacity), but the exact name from 64 GB to 2 TB will be microSDXC (Secure Digital eXtra Capacity).
The SD card class does not yet deliver enormous speeds. At present, SD cards are divided into five speed classes: DS (up to 12.5 MB / s), HS (up to 25 MB / s), UHS-I (10 MB / s to 104 MB / s), UHS-II (up to 312 MB / s) and UHS-3 (over 312 MB / s). Typically, microSD card packs are labeled Class 4 (minimum recording speed 4 MB / s), Class 10 (minimum 10 MB / s), UHS U1 (minimum 10 MB / s) or UHS U3 (minimum 30 MB / s). Unless you want to capture huge amounts of 4K or 1080p with 60 frames per second on the microSD card, any mircoSD Class 10 memory card will fit. Under Class 10, you should not fall apart.
Faster is better. In any case! If you do not currently have a 4K video camera, it can change in the near future. SD cards are almost eternal, they are not affected by humidity, magnets and tricks, so you might want to consider purchasing a slightly more expensive but faster microSD card. As I said, the Class 10 memory card is fast enough for smartphone photos, but its recording speed may not be quite large for other devices.
Sometimes slower (with slower recording capabilities) microSD cards are to blame for various video problems with "dropped" frames, uninchronized sounds, and so on. If your smartphone supports 4K or 1080p video at 60 frames per second, it's recommended to choose a UHS-I U1 memory card.
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