A portable electronic device comprising: a top module comprising: a front cover defining a first portion of an exterior front surface of the portable electronic device; a display stack attached to the front cover; and a frame member attached to the front cover and extending at least partially around a periphery of the display stack; a housing member comprising a wall, the wall defining: a second portion of an exterior front surface of the portable electronic device; a first portion of an exterior rear surface of the portable electronic device; at least a portion of an exterior side surface of the portable electronic device; a first interior surface set apart from a peripheral side surface of the front cover by a first gap of a first distance; a ledge feature extending below the frame member and attached to the frame member, thereby securing the top module to the housing member; and a recess between the first interior surface and the ledge feature and at least partially defined by a second interior surface that is recessed relative to the first interior surface and is set apart from a side of the frame member by a second gap of a second distance greater than the first distance; and a rear cover coupled to the housing member and defining a second portion of the exterior rear surface of the portable electronic device. a top module comprising: a front cover defining a first portion of an exterior front surface of the portable electronic device; a display stack attached to the front cover; and a frame member attached to the front cover and extending at least partially around a periphery of the display stack; a front cover defining a first portion of an exterior front surface of the portable electronic device; a display stack attached to the front cover; and a frame member attached to the front cover and extending at least partially around a periphery of the display stack; a housing member comprising a wall, the wall defining: a second portion of an exterior front surface of the portable electronic device; a first portion of an exterior rear surface of the portable electronic device; at least a portion of an exterior side surface of the portable electronic device; a first interior surface set apart from a peripheral side surface of the front cover by a first gap of a first distance; a ledge feature extending below the frame member and attached to the frame member, thereby securing the top module to the housing member; and a recess between the first interior surface and the ledge feature and at least partially defined by a second interior surface that is recessed relative to the first interior surface and is set apart from a side of the frame member by a second gap of a second distance greater than the first distance; and a second portion of an exterior front surface of the portable electronic device; a first portion of an exterior rear surface of the portable electronic device; at least a portion of an exterior side surface of the portable electronic device; a first interior surface set apart from a peripheral side surface of the front cover by a first gap of a first distance; a ledge feature extending below the frame member and attached to the frame member, thereby securing the top module to the housing member; and a recess between the first interior surface and the ledge feature and at least partially defined by a second interior surface that is recessed relative to the first interior surface and is set apart from a side of the frame member by a second gap of a second distance greater than the first distance; and a rear cover coupled to the housing member and defining a second portion of the exterior rear surface of the portable electronic device.