If you're looking to buy a massive (and I mean massive) Android phone, there aren't actually that many devices to choose from that push (or at least get close to) the 7-inch boundary. Actually, there are quite a few 7-inch and above devices that are sold in China, but most of them suck. Apart from the screen and battery, most of the absurdly large phones compromise on the processor and cameras. While Xiaomi's Mi Max phablet lineup doesn't have flagship-tier specifications, the compromises are acceptable given the low price tags. The Xiaomi Mi Max 3 launched in the middle of last year with a 6.9-inch display, Qualcomm Snapdragon 636, and Android 8.1 Oreo-based MIUI 9. Although it was only available in China at first, Xiaomi eventually started selling the product in international markets. After releasing the stable Android 9 Pie update for Mi Max 3 users in China, the Android Pie global update is now available.
You can download the latest MIUI 10.2.1 Global Stable release for the global Mi Max 3 from the link below. It's a recovery ROM that can be side-loaded from the MIUI Updater in Settings, or flashed via TWRP.
Download MIUI 10.2.1 Global Stable (Android 9 Pie) for the Xiaomi Mi Max 3
Thanks to XDA Recognized Developer yshalsager for providing the download link!