A hinge apparatus, comprising: a shaft cover, comprising accommodation recess parts; bases, disposed in the accommodation recess parts, wherein each base comprises relief spaces and first adapter parts, the first adapter parts face the relief spaces, the base comprises a synchronous slider and a limiting guide track, the limiting guide track is connected to the shaft cover, the limiting guide track is disposed at a side that is of the synchronous slider and that faces away from the shaft cover, and the synchronous slider is slidably connected to the limiting guide track; and swing arm assemblies, each comprising swing arm bodies and second adapter parts, wherein each swing arm body comprises a connection end and a free end, the connection end is close to the base, the free end is away from the base, at least part of the connection end is located in the relief space, the second adapter parts are connected to the connection ends, the second adapter parts are rotatably connected to the first adapter parts, the second adapter parts are connected to the synchronous slider, the swing arm bodies rotate relative to the first adapter parts via the second adapter parts to switch between a folded position and an unfolded position, and the second adapter parts synchronously drive the synchronous slider to move between a first position and a second position; and the synchronous slider comprises first helical surfaces, the first helical surfaces are arranged corresponding to the first adapter parts, each first helical surface is located at a side that is of the first adapter part and that faces away from the relief space, each second adapter part comprises a second helical surface, the first helical surfaces are in contact with the second helical surfaces, helix directions of the first helical surfaces on the two sides of the swing arm body are identical, helix directions of the second helical surfaces on the two sides of the swing arm body are identical, when the second adapter parts rotate opposite to the first adapter parts, the first helical surfaces and the second helical surfaces slide relative to each other synchronously, to enable the second adapter parts to drive the synchronous slider to move. a shaft cover, comprising accommodation recess parts; bases, disposed in the accommodation recess parts, wherein each base comprises relief spaces and first adapter parts, the first adapter parts face the relief spaces, the base comprises a synchronous slider and a limiting guide track, the limiting guide track is connected to the shaft cover, the limiting guide track is disposed at a side that is of the synchronous slider and that faces away from the shaft cover, and the synchronous slider is slidably connected to the limiting guide track; and swing arm assemblies, each comprising swing arm bodies and second adapter parts, wherein each swing arm body comprises a connection end and a free end, the connection end is close to the base, the free end is away from the base, at least part of the connection end is located in the relief space, the second adapter parts are connected to the connection ends, the second adapter parts are rotatably connected to the first adapter parts, the second adapter parts are connected to the synchronous slider, the swing arm bodies rotate relative to the first adapter parts via the second adapter parts to switch between a folded position and an unfolded position, and the second adapter parts synchronously drive the synchronous slider to move between a first position and a second position; and the synchronous slider comprises first helical surfaces, the first helical surfaces are arranged corresponding to the first adapter parts, each first helical surface is located at a side that is of the first adapter part and that faces away from the relief space, each second adapter part comprises a second helical surface, the first helical surfaces are in contact with the second helical surfaces, helix directions of the first helical surfaces on the two sides of the swing arm body are identical, helix directions of the second helical surfaces on the two sides of the swing arm body are identical, when the second adapter parts rotate opposite to the first adapter parts, the first helical surfaces and the second helical surfaces slide relative to each other synchronously, to enable the second adapter parts to drive the synchronous slider to move.