Long answer: Almost all iPhone cases currently on the market work with Duet. There are a couple exceptions, however, which mainly include cases that have a permanently hinged flap covering the Lightning Connector port. Some examples of these cases that don't play nicely with Duet: Otterbox Defender, Lifeproof frē, etc.
You bet it does. For both your Apple Watch and iPhone, you only need one hand to dock/undock. Thanks to the nano suction material on the underside of Duet, it's not going anywhere until you want it to.
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