Neill Blomkamp demonstrated in District 9 that he was able to weave social commentary into an interesting story without hitting you over the head with it.
Which he unfortunately forgot with Elysium, which by comparison was a bit heavy-handed. And if that wasn't bad enough, there was a serious lack of logic–why would anyone build a space station without the ability to defend itself?
Because the script needed it to, that's why!
And what was even worse is that the story didn't even try to explain why that was the case.
Fortunately the leaps in logic that Chappie makes aren't so blatant–though they're there–because the character is so fully-realized that you won't at first notice them.
That being said, it's overall an very enjoyable movie about what it is that makes a person truly human, AI (Artificial Intelligence), and so on.
The special effects are pretty remarkable–I assume that Chappie is done with motion capture because there's no way CGI otherwise moves as smoothly, as fluidly as Chappie tended to move.
Though when all is said and done, it's nothing that you haven't seen before, though it the way that Blomkamp assembles the varied pieces that makes the movie as engaging as it ends up being.
Chappie, when all is said and done, is a more enjoyable movie that Elysium, though not quite up District 9 standards.
And you know what? That's okay because that's a pretty high goal to reach.