This is an amazing addition to the K3. While it has some downsides, overall I find it very useful and works as advertised. I have two main uses: 1) as a way to remotely control the camera and change [some] settings. Very useful when you don't want to disturb the camera OR when the weather is bad and you don't want to just stand around a tripod and wait in the cold. Find a convenient place (e.g. in a car) nearby and wait for the moment. The live view on the big screen also helps you to check the composition, exposure and focus. There are limitations because the resolution in live view is pretty bad and the colors are very imprecise (washed out). But it's still a useful tool. Also useful as a backup in case you forget your remote shutter release. 2) Access and download images directly to your mobile phone. In this respect, it works the same as other Wi-Fi cards. But the two features together are unique and absolutely worth the dollar.
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