Branch is able to provide device-level view-through attribution for installs only, for up to 24 hours from impression to install. This is what is available via the MMP API that Facebook has exposed. It's also possible that if other app events (such as opens) occur shortly after an install, we can attribute those back to the same impression/view.
Facebook does not allow us to use impression trackers. Facebook will only provide impression data for certain app events via MMP API. Thus, we will not be able to track the large majority of web conversions attributed to a Facebook impression. This is specifically not allowed by Facebook. There unfortunately aren't any workarounds to this.
Updated almost 3 years ago