I like this a lot. It's an interesting concept, I've seen something similar but not this detailed. However, I do have a few things to suggest.
First off, what bugs me most is the reflection of the fingers. To me, from the angle that the viewer sees, I think that you'd see more of the bottom of the fingers than the nails. The thumb bothers me most in this regard.
Secondly, I don't quite think you took the liquid far enough. It seems like only a small part of the image is used for the "surreal" aspect, and the rest is boring. I do think that the overall technique is great, much better than anything I can currently muster, but it seems a bit limited in terms of the imagination.
In a few words, I think that you did a great job on drawing the image, but it seems to lack in imagination. It was a good idea, but you might try making it a little more colorful, making the surreal parts of the image stand out against the tablet or the normal surroundings.
Love the concept of this! It's like a modern-day-technology version of those 'drawing a drawing of me drawing with the drawing I'm drawing coming to life' drawings that I see every now and again. I agree with some points that Stinker made about the reflexion and such, and it'd be great to see a tad bit more detail here and there, but it's still a great piece
that's really good, especially the Idea is great. Now critique should also mention some improvable points. So ... you just mirrored the hand - but the reflection would look different to the real hand, as one would see more of the inner part of the hand and the fingers. Also less of the thumb's nail (you would rather see it's side) ... and you could try to overpaint the water, which is this filter combination, isn't it? and maybe make a more uneven change from tablet to the water, means not one smooth edge ... I hope you understand me . I hope you don't mind my words, well, to sum it up I can tell you that this is really good