Unity SDK for XIAOMI provides an easy way to intergrate with XIAOMI’s IAP and Unity Ads in Unity editor. This is the Alpha v0.0.1 build.
You can download the the unity package here and the docs can be found here (IAP) and here (Ads).
If you have any question, feel free to contact us at iapsupport@unity3d.com for IAP and chinaads@unity3d.com for Ads.