Software
Settings of the Eye-Fi card such as wireless network access, selecting upload location on local computer and configuring photo sharing sites is done through software called the Eye-Fi Center which is available for both Microsoft Windows and Mac OS X. Recently mobile access (in beta) has been added via a browser by visiting: http://m.center.eye.fi
Before use of any Eye-Fi card the user must "register" on the Eye-Fi website, in doing so the card software demands the firewall to be opened for the Eye-Fi software, the same happens every time the user needs to reconfigure its wireless network with the network data ending up sent and stored to Eye-Fi servers and that happens by default to every single picture too.
Eye-Fi offers an iPhone program, but it is only available in the US, UK, Canada, Australia, and Japan App Store. There is also an App available for Android in the Google Play Store: https://play.google.com/store/apps/details?id=fi.eye.android
Under Linux, the EyeFi card can be configured using eyefi-config, which allows viewing the logfiles and changing the wireless settings. To receive images from the card, there are several alternatives, EyeFiServer (in Python), iiid in C++), RyFI (Ruby based) and Node-Eyefi (NodeJS). However, the UploadKey and TransferMode must still be defined from within Windows/Mac for the first use: although 'eyefi-config -k' has the capability to "print card's unique key", this isn't the UploadKey that is needed.
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