All Nextbook tablet computers that are sold in the United States are equipped with a memory expansion slot that accommodates a microSD memory card. Among the Nextbook tablets available for purchase in the U.S. include the Nextbook7, Nextbook8, the Ares series and the Flexx series, as of June 2014. Nextbook is a brand of affordable tablet computers that run on Android and Windows 8.1 operating systems.
The Secure Digital Association, or SDA, officially recognized the microSD as a standard memory card specification in July 2005. Technically, microSD cards are actually categorized as secure high capacity, or SHDC, card rather than an SD card. SD cards have a standard memory capacity of 1 to 2 gigabytes, while microSDs can have a capacity of up to 128 gigabytes. Considerably smaller than SD cards, microSD cards are commonly used in mobile devices such as smartphones and tablets.
Tablets under the Nextbook brand are manufactured by Yifang Digital Technology, Inc., which operates from its headquarters in Shenzen, China. Its U.S. branch is under the westernized business name of E Fun and is based in La Veren, California. E Fun designs and manufactures fun lifestyle electronic products that are affordable, according to its website. Apart from the Nextbook tablets, E Fun U.S. also markets the APEN Digital Pen.