Great question — answering as the UphillTech team:
The short of it is that each of the iTunes / App Store Affiliate Programs is country specific so using the US/LinkShare program will only affiliate sales made in the US stores. You will need to use the UK/Tradedoubler program (and appropriate tracking parameters) to earn commissions for sales in the UK store, the AU/DGM program to properly affiliate traffic for the Australia store, etc. To fully capitalize on your international traffic and correctly affiliate those clicks you will need to have a relationship with the multiple region-specific affiliate networks (4 total) and have been approved into and use the appropriate affiliate tracking parameters. Then, as you mentioned, you'll need to...
Full answer by Geniuslink: https://stackoverflow.stackexchange.com/a/16431185 (CC BY-SA 3.0).
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