I'll add, by the way, that the stock HTC 2D pano tool is also absymal. It appears to make absolutely no effort to warp images, and simply aligns and fades them instead, leading to clear zig-zags in what should be straight lines like horizons.
The thing is, much MUCH better results should be possible. Attached is a pano shot not with the HTC One X, but with my Sony RX100 compact camera. (I've resized it to the same height as your pano.) It's a much more challenging subject, although nowhere near as bad as expecting to get a decent pano standing in the middle of a small room.
My image is -- other than brightness / contrast / color adjustment because there was a strong difference in exposure level and the bright sun / water biased the exposure too dark -- straight out of camera. No hand-tweaking of alignment was done, nor any local retouching of any kind.
It's stitched by the camera itself, which doubtless has a far less powerful processor than the HTC One X does. If the Sony can do this, the HTC One X should be able to do far better -- but so far it can't.
Head of an Android household: HTC One X+ International 64GB, HTC One X International 32GB, two hopelessly unstable Asus Eee Pad Transformers (32GB and 16GB, each with keyboard docks; remember -- friends don't let friends buy Asus), Samsung Galaxy Ace, and a Fuhu Nabi 2.