This is all as of version 6019.
Noticed that a decent chunk of Facebook App on Android phones have an "unknown" platform version, even though it seems pretty clear that the Android version is either "6.0.1", "5.1.1" , "5.1" or "6.0".
We have other Facebook App on Android UAs in the same date range that do have a proper platform version (highest one is "5.0", so perhaps browscap just isn't configured to parse out the newer versions of Android?).
I also noticed that browscap doesn't detect the "Version" of the Facebook App very well (All of the recent UAs we have that are Facebook App show "0.0" as the browser version). Should this version number be the version on the end of the string (i.e. "107.0", "106.0", etc...)? I noticed that some other UA parsing libraries do use that as the version of the browser (some are using the Chrome version though, which perhaps isn't correct when they're being marked as "Facebook App").
Here are the strings: