They were probably inspired by Grave Encounters. The basic idea behind it is in fact the same: A film crew, which is searching the supernatural but does not believe in it, will learn that monsters/demons/ghosts are real.

And in the end, [spoiler] this film turned out as just another Satanic cult movie... [/spoiler]

Basically, however, some other commenters are right. Nothing that has not seen before and always the same. Running away, fighting, screaming, running away, fighting, screaming, etc.

These are probably the weakest fucking monster of all, [spoiler] since all are more or less killed quickly [/spoiler] and that with... well... really cliched methods.

However, before it even "starts", we are fed with completely irrelevant background information for the first 30 minutes of the film, which is actually nothing that contributes to the importance of the story and the "interviews" are also uninteresting.

The end and the dissolution of what's going on, went as quickly as it came. You do not know even how and why, it just became clear that [spoiler] everything is a set-up from Devon and his satanic cult and that's it... [/spoiler]

I can unfortunately can not say anything about the acting, because I saw the German version and in many cases of found footage movies due to rapid camera movements the actor's power is transmitted via the voice.

Regarding the effects: I've seen worse.

My conclusion: I didn't had any satisfying feeling after watching this, because the end is just _bad_ and pointless. I also have forgotten this film again pretty soon.