MileagePlus X.
It’s an eGift card app (not a shopping portal, that’s MileagePlus Shopping), similar to Gyft and Swych, but you earn United miles on gift card purchases depending on merchant plus whatever points or miles you earn on your credit card; and unlike Gyft and Swych, which sells gift cards in fixed denominations, MPX allows you to buy the exact amount down to the penny for many retailers, so you’re not left with less or more gift card balance than you need (some merchants still sell only fixed amounts).
For a while, it was
the MR points earning monster for a lot of us with personal Amex Platinums, because MPX would code as an airline ticket and earn 5x MR on the Plat, United miles depending on merchant, and whatever else cash/points/miles you could earn when you spent the gift cards through shopping portals.
Less lucrative, but still a good deal, was how MPX behaved on Chase cards. MPX would pass through how a gift card purchase coded to the category of the merchant for which you were buying the gift card.
So if you bought a gift card for Panera Bread or Starbucks, MPX would code that transaction on the CSP and CSR as dining and trigger their dining category bonuses (2x and 3x respectively). If you bought Uber or AirBnB gift cards, MPX would code that purchase as travel and earn you 2x on the CSP and 3x on the CSR/CIP. MPX or Chase stopped coding this way a few months ago... but it may be back!
(By contrast, Gyft and Swych never distinguished the merchant category coding for each gift card they sold; these two apps code as platforms and I believe trigger something in the internet/cable/phone category so earn 3x on the CIP, 5x on the CIC/Ink+ for every merchant’s gift card purchased on the platform.)
So just an example of how this might work: if I’m out for lunch at Panera Bread and my cashier rings me up for $9.80, instead of pulling out my CSR and earning only 3x UR, or paying with a Panera Bread gift card I bought at an office supply store for 5x UR on the CIC/Ink+ or grocery store for 5x UR on the Freedom this quarter (and then having an odd balance left over), I pull up the MPX app see that it earns me 5 UA miles/$1, buy an exactly $9.80 eGift card using my linked CSR for 3x UR (if it’s really passing on the coding again) — and because I have a United MileagePlus credit card linked to my MPX account (but don’t have to pay with it), I get a 25% bonus in miles — then show the eGift card on my phone to the cashier to pay. So in all, I’d earn about 61 UA miles and 29.4 UR from lunch.