Download latest Android application for Xiaomi Mi Router v.2.2.7 from here, here or here. (12 MB) Download previous firmware v.2.2.6 from here.
Xiaomi Mi WiFi router curent firmware version: 2.8.9 stable
Tip: to use the application in English, make sure that your device system language is English. If not, the application will start in Chinese. It looks like this newer version is chinese only.