Any tool to spy FB Ads ?

Hello, I'm pretty sure I have already seen that before but i'm not finding it anymore.

I'm looking tool to get FB audience from ads posted by someone else..
I know that a soft like FBCandy grabs CIDs but would like to get the audience.

Maybe it does not exists at all ^^.

Try Bigspy if you are starting
If you are on a budget, you can go for Adplexity.
There are multiple options, but this two are a good starting point

Adplexity provide different versions for the mobile,native,destop.this is the king of spy tool