Xmind does not support synchronization at this time. You may need to transfer your mind maps from desktop to your Android phone.
1. Transfer via Wi-Fi Transfer
You can use Wi-Fi Transfer to transfer your Xmind file from one device to another by connecting the same WiFi.
1) Tap the three dots on the upper right corner,
2) Tap Wi-Fi Transfer,
3) Follow the instruction on the page of WiFi Transfer,
4) Download or upload your Xmind files.
2. Import Xmind file in Xmind for Android
1) Transfer your Xmind file from desktop by using USB or Bluetooth,
2) Tap the three dots on the upper right corner on Xmind for Android,
3) Select Import,
4) Find your desktop Xmind file to import in Xmind for Android.