I wanted to know if I could use a contactless reader on an iPad 3, I just have a lightening reader now, and want to upgrade
According to the Square Hardware Compatibility checker page, the contactless reader is available for the iPad 3, but the lightning port swiper isn't, since the 3 can only go to iOS 9.
Square also has a WindFall stand kit if you need the whole shebang, but really any case for the iPad 3 will work for the contactless reader. With a headphone swiper, you'll have to make sure the case has room for swiping.
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