Quote: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.

Full reading: https://www.anandtech.com/show/13441/sandisk-unveils-extreme-microsd-cards-with-a2-spec