The United Airlines MileagePlus X app is an additional way of earning United miles, in addition to traditional methods like booking travel or using an airline-co-branded credit card, like the United Airlines Quest Card. Users can earn miles on in-store and online purchases, such as dining, online shopping, last-minute hotel reservations, using featured apps, and buying eGift Cards. The app was launched in 2019 and at the time had more than 900 opportunities for mileage earnings.

It also required users to pay for purchases through the app, but that is no longer the case. To promote the app in 2019, United created an ad which ended saying, "The United MileagePlus X app, your ticket to earning award miles for the things you need every day, on the go." According to the United website, users can earn up to 10 miles per dollar spent in a simple, three-step process: Download - Download the app on the App Store or Google Play Store and enter your MileagePlus account information.

Search - Search through our catalog of eGift Card merchants, restaurants, online retailers and last-minute hotel deals. Spend - Make purchases in the app, on a website or in- person. You'll earn miles for every dollar you spend.

Further, earning is broken down into four categories (United recently cut the app-to-app category): eGift Cards: Buy eGift Cards from over 270 different merchants like Sephora, Apple and Walmart. MileagePlus Dining: Link your credit card and earn up to five miles per dollar on dine-in.