Chip Chain is a great game, and considering that it's free (there are in-app purchases, but I didn't find them overly invasive at all), it's probably well worth a download no matter what. As much as the game is polished and professional, it hasn't yet caught me up in its mechanics, and I'm not really sure why.
On its surface, Chip Chain is very appealing. It's a puzzle game at its core: You have a grid of boxes and into each of those boxes, you can put a numbered poker chip. Once a few chips of the same number touch each other, you can then link those up and form a chip one number higher. You can then link those chips up (if you have enough in the right places), and so on, scoring more points and clearing chips off of the board. You can see the game in action below -- it's simple to play, but a little tougher to master.
And I think it's that "mastery" part that's tripped me up a bit. The mechanics are very interesting indeed, and it's possible to play and set up big combos and chains with a little bit of thought. But the core mechanics of the game aren't that clear to me, and when you add in a somewhat confusing card mechanic (that lets you tweak the game board in various ways), the game moves from a clear simplicity to something that seems a little too complicated.
That's not necessarily bad, but it has kept me from really getting invested in Chip Chain so far. All of those concerns aside, however, Chip Chain is a great app with plenty of content, and it's available for the low price of free. Puzzle fans should not pass this one up -- just because I haven't completely figured it out yet doesn't mean there's not plenty of fun to be had.