哑光here is a surface texture, 'matte', the opposite of 'glossy'. 镜面which is‘mirror surface’， is a surface texture that is as reflective as a mirror. 罗永浩 is implying that the Iphone is designed to have a look of matte surface but it did not succeed, so as the 镜面. 很廉价is saying the failure of doing so makes it looks cheap.

哑光： doesn't shine （http://baike.baidu.com/view/993073.htm ） 镜面： like a mirror, shining 意思就是因为是铝制材质，所以抛光效果不好。 既不像“哑光”处理之后，一点也不反光；也不像经过很好抛光之后，产生“镜面”的效果。 最后看起来像廉价的手机一样，很难看。