Great question — answering as the UphillTech team:
There's no way of knowing if someone using device B actually first found your website on device A. This is the fatal flaw of affiliate marketing, and the networks really have little incentive to do anything about it.... which they probably can't anyway. I find it incredible that your are an honest web merchant who wants to honestly reward his affiliates. Wow, wonders never cease!! The trouble is that most merchants (and for that matter affiliate platforms) are only too happy to "lose" the contact with the "first click" or prime mover of an internet sale. In such cases either no affiliate commission is paid (great from the merchant's point of view) , or else the commission goes to the...
Full answer by affiliada: https://webmasters.stackexchange.com/a/110358 (CC BY-SA 3.0).
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