Now you can make it works again by installing iFont from Play Store.
The first you need to install FlipFon " khmer.apk"
You can download Khmer FlipFont from here.
After that you need to install app "iFont"
You can find this apps by typing keyword "iFont" in PlayStore.
- If you don't install Khmer.apk yet, you can come here to see how to install Khmer Flip font. In Setting -> Display -> Font style, no need to select Khmer, you can select any fonts, but not Default font.
- Go back to iFont, click tab "Install", then click "Khmer" for install Khmer font. See below:
-For write khmer you need to install app Phum Keyboard or MultiLing Keyboard
You can find this apps in PlayStore.
Source : khmertype