MOBI is an eBook format that supports several eBook reading devices and gadgets. It also supports in mobile phones and PDAs. Although it is a file extension of Mobipocket Reader, most other eBook readers also support this file format. It also contains DRM to protect the digital right of the eBook. This format is officially discontinuing from the year 2011.
Free, fast +
You can use it on electronic devices such as computers, tablets, and mobile phones.