Integral Memory claims biggest microSD record with new 512GB card | Android and Me. It will be expensive; but, a tiny thumb-nail sized micro SD card with 512 Gigabytes of capacity? Wow. This will be a good reason to insist that your Smartphone have a micro SD slot. In fact, if it isn't too expensive, this would be a great substitute for the 128 GB card in my ultralight computer. Or, this would hold thousands of photos on my digital camera. To date, the biggest storage card available was 400 GB from SanDisk. Let the storage wars begin.