I'm going to go out on a limb here and say that any gifts we get won't be Halo related. They're done with Halo, and the app is called Bungie Mobile. That means that they'll be updating it to include stuff other than Halo content eventually. It's not called
"Bungie Halo: Reach Mobile" for a reason. I seriously doubt that we'll ever get more Halo gifts from Bungie.