Novi
As stated on HTDC's DCIL section:
"Novi Financial, Inc. (“Novi”) is changing the way money moves. Novi intends to offer a new digital wallet service for the diem payment system. Novi is from Facebook, so you’ll be able to access it from your favorite apps.
Novi’s motto is: “A connected wallet for a connected world.”
Conclusion: Well let you know how we feel about a Facebook centralized cryptocurrency payment network if we ever try it out.
Sources: DCIL Participating Companies - HTDC