Mediocre film. The effects were great. Acting is great.
More drama than horror. Lack of thrill the story is too short to get the audience's attention,
I haven't seen all zombie films but this seems like a somewhat different approach. Yes they are all full of conflict as movies showing people trying to survive a zombie apocalypse usually are. But having a family deal with the aftereffects and the current threat of a potential relationship break up during an apocalyptic event where the couple is forced to stay together seems different. I guess they've explored that somewhat in long series such as the Walking Dead but zombie movies in general seem more packed with action than drama. The Walking Dead though, at some point, became too soap operaish to be satisfying to me. I couldn't finish it. Outside manages to be satisfying in the length of a movie rather than having to invest loads of time as in a series.
The main character, the dad, can't control his anger at that situation nor see that the event they are experiencing far eclipses a breakup of a relationship. Seems he was probably a somewhat unhinged person who couldn't or wouldn't control himself prior to the zombie apocalypse and now he sees a chance to try to control his spouse but she's not having it (or at least trying not to).
They were all excellent actors but I really enjoyed the dad character the most as that character was propelling the story along. The actor playing him did such a great job with that role too. I'd recommend this movie. I think it has a nice balance of thriller action and drama.