Command (AFSOC) purchased an initial supply of over 3,000 iPad-based EFBs which were launched in December 2011. In a similar acquisition, Air Mobility Command initiated a contract for up to 18,000 iPad-based EFBs. The Air Force Special Operations Command internally developed a secure method of transferring the National Geo-Spatial Intelligence Agency's (NGA) monthly Flight Information Publications (FLIP) dataset to all its users worldwide. After trialing iPads as EFBs in 2011, Delta Air Lines announced in August 2013 it would replace a policy allowing pilots to use personal tablets as EFBs. Delta planned to provide new certified EFBs to all of its pilots by May 2014, after FAA approval in February. Early risk of breakage to iPads used as EFBs was addressed through rugged case design. However, the purchase of iPad from AFSOC was cancelled in February 2012 due to security concerns, where Russian-made software procurement issues may cause potential risks to expose end users. Design features EFBs were initially divided into a number of hardware classes and software types. However, later EFBs simply were categorized as "Portable" (PEDs) or "Installed". Portable can be considered to consolidate the previous Class 1 and 2 distinctions, while Installed is equivalent to Class 3. These simplifications made to reduce confusion and to harmonize with already-released EASA and ICAO guidance. Legacy EFB hardware classes were: Class 1 – Standard commercial-off-the-shelf (COTS) equipment such as laptops or handheld electronic devices. These devices are used as loose equipment and are typically stowed during critical phases of flight (below 10,000 feet). A Class 1 EFB is considered a Portable Electronic Device (PED). Class 1 EFBs, such as Cockpit iPads, may be used to display Type B applications in critical phases of flight provided that they are 'secured and viewable'. Class 2 – Portable Electronic Devices, and range from modified COTS equipment to purpose-built devices. Mounting, power (ship's power as primary) or data connectivity of an EFB typically requires the application of an STC, Type Certificate or Amended Type Certificate. (ref: FAA Order 8900.1) Class 3 – Considered "installed equipment" and subject to airworthiness requirements and, unlike PEDs, they must be under design control. The hardware is subject to a limited number of RTCA DO-160E requirements (for non-essential equipment—typical crash safety and Conducted and Radiated Emissions testing). Class 3 EFBs are typically installed under STC or other airworthiness approval. EFB may host a wide array of applications, initially categorized