Devices, kits and methods described herein are provided for treatment to skin, including but not limited to wound healing, the treatment, amelioration, and/or prevention of scars or keloids. A book-like packaging, applicator and/or tensioning device can be used to apply a dressing to a subject. The packaging, applicator and/or tensioning device applies and/or maintain a strain in an elastic dressing, and include undulating edge configurations to reduce peak stresses applied to the skin compared to traditional dressing shapes.
