Western Digital’s SanDisk division on Friday unveiled its first lineup of microSD cards that are compliant with the App Performance 2 (A2) specification. The new SanDisk Extreme cards are designed primarily for smartphones, so they do not offer very high sequential read/write speeds, yet in accordance with the A2 requirements, they offer rather high random performance for a removable memory card, making them better suited for running apps off of them.

The new SanDisk Extreme microSD cards with A2 badge will be available in 32 GB, 64 GB, 128 GB, 256 GB, and 400 GB capacities. The new memory cards use the UHS-I bus and are rated for up to 90 MB/s sequential read speeds as well as up to 60 - 70 MB/s sequential write speeds, depending on the capacity (32 and 64 GB cards are a tad slower). The cards also carry the V30 badge and therefore support a minimum of 30 MB/s write speed.

More importantly, in line with the A2 requirements, the new SanDisk Extreme microSD have a random performance of at least 4000 read IOPS and 2000 write IOPS (keep in mind that Western Digital does not disclose actual performance of the card, which may exceed A2 requirements). In addition to enhanced random performance (vs. 1500/500 read/write IOPS mandated by the A1), A2 cards are required to support such functions as command queuing (with a minimum depth queue of 2 and a maximum depth queue of 32) to optimize random read performance, caching to hit write performance targets, as well as self-maintenance capabilities.

The SD Association’s A2 spec was designed specifically to improve performance of applications that are installed on microSD cards. In fact, the latest versions of Android only allow users to install apps on A1/A2-badged microSDs. With enhanced random read/write speeds, the new cards will be a better fit for apps that perform a lot of read/write operations and will therefore significantly improve user experience. Meanwhile, just like their predecessors available today, the new SanDisk Extreme cards are compliant with UHS Speed Class 3 and Video Speed Class 30 specs, thus providing at least 30 MB/s sequential write speed and simultaneous interleaving of eight different files, which is useful for 360° videos, or even numerous high-quality Ultra-HD still pictures taken simultaneously.

To further ensure that the new SanDisk Extreme cards are suitable for photographers and drones that happen to work in rough conditions, they are designed to operate in the range between -13ºF to 185ºF (-25ºC to 85ºC).

SanDisk Extreme microSD Cards with A2
  400 GB 256 GB 128 GB 64 GB 32 GB
Sequential Read Speed up to 90 MB/s
Sequential Write Speed 70 MB/s 60 MB/s
Minimum Sequential Write Speed 30 MB/s
Random Read Speed At least 4000 IOPS
Random Write Speed At least 2000 IOPS
Operating Temperatures -13ºF to 185ºF (-25ºC to 85ºC)
Interface UHS-I
Availability Q4 2018
SDA Labels A2, V30, U3

Traditionally for SanDisk Extreme microSD cards, the new products will ship with the SanDisk Memory Zone (helps to organize data on Android-based devices and effortlessly back it up to the card) and RescuePRO (simplifies recovery of files that were accidentally deleted) apps.

Western Digital Japan plans to start sales of its SanDisk Extreme microSD cards with A2 badge on October 12. It is unknown when these cards hit other markets, but it is highly likely that this is going to happen shortly. Western Digital is the first company to announce its A2-compliant microSD cards officially. At least one vendor has demonstrated such cards on various occasions, but so far has neither listed them nor started their sales.

Related Reading:

Source: SanDisk, Hermitage Akihabara

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  • MrCommunistGen - Friday, October 5, 2018 - link

    Huh. That's interesting. Still, I feel like this is "too little, too late" because by this point a lot of devices no longer have a microSD card slot.
  • imaheadcase - Friday, October 5, 2018 - link

    They don't because of the thing they literally just fixed with this new spec. Its a shame to because so many people use microSD cards to back up photos/videos because for a non-techy its easier to backup that way vs other means. Its pretty much the go-to family asked question "I got a picture i want to save or print how do i do that".

    That said, SanDisk Memory Zone is cancer, while good intended, it wants total control over files each time instead of using default file managers.
  • brakdoo - Friday, October 5, 2018 - link

    Nah, (automatic) cloud backup for pics and vids is cheaper, easier and more reliable but you need a good internet connection...
  • imaheadcase - Saturday, October 6, 2018 - link

    You seriously don't have a clue about phone usage, majority of people don't even have a smart phone and use pay as you go plans.
  • Fergy - Saturday, October 6, 2018 - link

    Android has been making SD cards harder and harder to use. I never had a problem with the speed of any SD card.
  • norazi - Friday, October 5, 2018 - link

    This is useful for my Surface Go since it only has a 128gb SSD (although it is a fast NVMe drive). Even with my current 256GB Samsung EVO+ U3 drive, apps running off the microSD are significantly slower vs off the SSD.
  • Tams80 - Friday, October 5, 2018 - link

    This isn't going to make them that much faster as NVMe drives are in a different league entirely.
  • jabber - Saturday, October 6, 2018 - link

    At lot folks still use such devices as proper cameras. That's the market for these.
  • zodiacfml - Saturday, October 6, 2018 - link

    Im a fan of expandable storage but this product is too late. Builtin memory has become decently large and a lot faster.
  • rpg1966 - Saturday, October 6, 2018 - link

    Lol, because nobody needs more than the piddling amount of in-built storage in today's phone, amirite?

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