Windows Mobile 5 was Microsoft's latest operating system for handheld devices in 2005, which replaced Windows Mobile 2003. One of the broadest features WM5 introduced was a unified underlying platform between the three kinds of devices it supported: Microsoft Smartphones, Pocket PCs, and Pocket PC Phones.
Windows Mobile 5.0, originally codenamed "Magneto", was released at Microsoft's Mobile and Embedded Developers Conference 2005 in Las Vegas, May 9–12, 2005. Microsoft offered mainstream support for Windows Mobile 5 through October 12, 2010, and extended support through October 13, 2015. It was first offered on the Dell Axim x51. It used the .NET Compact Framework 1.0 SP3, an environment for programs based on .NET. Windows Mobile 5.0 included Microsoft Exchange Server "push" functionality improvements that worked with Exchange 2003 SP2.[3] The "push" functionality also required vendor/device support. With AKU2 software upgrades all WM 5.0 devices supported DirectPush. This version featured increased battery life due to Persistent storage capability. Previously up to 50% (enough for 72 hours of storage) of battery power was reserved just to maintain data in volatile RAM.
