I notice that you have a specific style of putting a color against a background of the same color. I personally love black on black.
There are ways to make the picture look as though it is working together, better, though. First of all, there are very bright pinks, blues, and purples behind the HTC, but they are not making any impression on the reflective surface of the HTC.
Also, it is obvious the HTC was flipped, because the words are mirrored.
According to the lighting on the HTC, there should be a massive shadow behind it, but I don't see it, and the shadow is inconsistent with the shadow of the bonsai and the rock.
The composition isn't very balanced. I think it would be better if the HTC was more centered, and the tree was further from it. The person seems out of place, and because the picture is so small, it is hard to see details of the human. Because the colors are so bright on the human, it becomes a little bit distracting.
However, this is a nice clean photo manip, and it appears as though your technique is improving. Keep on creating =)