After beating it a few days ago I'd say yes it's worth it, assuming that the description of the gameplay peaks your interest.
Good:
Gameplay wise it is able to build a lot of tension, and really requires you to be observant and always thinking on your feet. I do think they could have potentially made it harder to extend the length of the game, but I felt just trying to get all of the survivors through the 7 areas was a good challenge that maybe in total took about 5 hours.
Graphically it's one of the best looking games I've played on Mobile - doing a fantastic job of adapting Alien: Isolation's visuals and sound effects to a smaller platform. Voice acting is great.
Annoying:
The game requires a lot of trial and error, which is fine, but there are a few stages that kind of take some time to get going at the start.
Controls are mostly fine, but I felt like the camera speed for when your in Amanda's POV was a little too slow, and caused me to die a few times because I couldn't turn my head fast enough to close a vent.
Story wise it is pretty bare bones.
All and all I thought it was very much worth the 5 bucks. Maybe it's a bad comparison, but I tend to compare game purchases with going to the movies. Nowadays it costs you anywhere from $7-$13 just to see a 2 hour long movie. So an interactive Alien game that lasts twice as long is a good deal to me.