A free program for Android, by mydroid.
Farsi Keyboard: Persian Typing is a fast, free, and easy-to-use keyboard for the Persian language. It's the perfect tool for anyone who wants to type in the Persian language, either for personal or professional purposes. With this keyboard, you will have an easy time writing messages in the Persian language, regardless of what device you are using. It works on all Android devices, and it's free to download and use.
You will be able to choose from a variety of themes and also customize the font style and color of the keyboard. It has more than 3200 emojis and smileys that you can use in your messages. It also has a built-in translation function that will allow you to translate your messages into any language, even if the person you are sending them to doesn't speak that language.
