...
Here is the meaning on WAM interface audience builder
IDFA = @weboid (= Mobile ID)
User Apps (Xdevice) = Match Cookie & IDFA, (for example : user have 1 iphone & 1 desktop, counted as 1 user).
...
in WCM collect, there is a few parameters that can identify a mobile user.
g.ism: is the hit a mobile one
g.did: device identifier
...
app =Xdevice profile with at least 1 IDFA (this profile can have other IDFA and/or AfficheW)
User Web = Xdevice profile with at least 1 AfficheW (this profile can have other IDFA and/or AfficheW)
Xdevice, Weboid and CRM ID
...