The WeDict Pro for iPhone/iPod touch brings you a pocket dictionary with multi-language. This version uses the same dictionary format as StarDict. A basic English-Chinese and the WordNet 2.0 English-English dictionary come with the application. The pro version is able to add more dictionaries by downloading form internet or uploading via wifi network.
You can download and install WeDict Pro ipa.file here.
For installing the other dictionary in your iPhone such as English-Khmer, Khmer-Khmer as follow:
Open Wedict Pro 1.5 => Go to setting at the bottom right
Click on Dictionaries
Click on Download
Click on "Download from URL"
Enter the following URL : http://khmeriphone.googlecode.com/files/ChuonNath_Dico.zip (For Khmer-Khmer Dictionary), or http://khmeriphone.googlecode.com/files/EnglishKhmerDico.zip (For English-Khmer Dictionary) And then Click Go
When download finished, Click Done
Then quit the Application and Re-Open it
The Dictionary is here
