Due to my inexperience with facebook ads, I had some problems with configuring the app correctly at first, but within few hours I got all the information I needed to solve the issue.
The app does what is says, and all the improvements I need, most of all captions in languages other than english and more flexibility to edit the creatives, are already in their "working on it" list.
At the moment I see this is more as an investment than as the purchase of a fully developed product, but I'm confident that I will use this app more and more, once the new or improved functions will be implemented.