LRF is an eBook format used by Sony’s older eBook readers. It supports DRM (Digital Rights Management) and allows users to read digital books on Sony devices. LRF files are now largely obsolete, replaced by more popular formats like EPUB and PDF for eBook distribution.
MOBI is an ebook format used primarily by Amazon Kindle devices. It’s based on the open standard for digital publishing and allows for content reflow and support for images, links, and embedded fonts. MOBI files are widely used for ebook distribution and are compatible with various reading apps.