If your mobile smart device is as much of an entertainment hub or recorder of high resolution photo, video and audio as mine, then you'll likely find your onboard memory and microSD card storage filling up rather quickly. SanDisk has chosen the Mobile World Congress in Barcelona, Spain, to announce some storage anxiety relief in the shape of the world’s largest capacity microSD card.

The new 128 GB addition to its Ultra microSDXC UHS-I memory card range has been designed for Android smartphones and tablets. It features 16 layers of vertically-stacked memory die, each said to be thinner than a human hair and boasts some rugged credentials, including being water-, temperature-, X-ray-, magnet-, and shockproof.

SanDisk reports that its new removable storage is twice as fast as your bog-standard microSD memory card, with the promise of read speeds of up 30 MB/s (though write speeds are simply listed as "lower"), and Class 10 performance that allows for lag-free Full HD video capture.

An update to the company's Memory Zone app has also been revealed, which features something called OptiMem. This can automatically transfer digital media from internal memory to removable storage and continuously monitors device memory levels and alerts users when a predefined threshold is reached.

The 128 GB Ultra microSDXC UHS-I memory card is available immediately for a suggested retail price of US$199.99.

SanDisk has also detailed what's described as its fastest, thinnest and most sophisticated embedded storage product so far. The 64 GB iNAND Extreme embedded flash drive offers sequential read speeds of 300 MB/s and write of 80 MB/s, or random read speeds of 6,000 IOPS and write of 3,000.

It's based on the new eMMC 5.0 HS400 specification and features dual CPU and dual channel hardware architecture. General availability is set for the second quarter of 2014.

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