The great thing about XDA-Developers.com is the open attitude towards community. You don’t have to sign up as a member to read the posts, although a free login is required to download apps and view screenshots.

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The real benefit of this community is its attitude to cross-compatibility and acceptance of the multitude of devices running Windows Mobile.
While the majority of posts surround the HTC manufactured devices (for example the HTC HD2 or the HTC Diamond) there are also sub-forums dedicated to Windows Mobile phones made by Toshiba, Samsung, Acer, Song Ericsson and others.
A typical sub-forum will include a General board for discussion about the particular phone and perhaps the community itself, a board to discuss accessories for the phone in question, a board discussing – and often previewing and making available for download – applications and themes for that specific Windows Mobile phone, and finally a board featuring downloads to custom-developed versions (known as ROMs) of Windows Mobile specifically for that model of device.