The new version of iPhone OS 4.0 beta 3 update SDK was released today for registered developers.
The iPhone OS 4 SDK offers bug fixes. New features include file sharing between the desktop and iPhone via iTunes, iPod media player widgets, minimal multitasking and a screen orientation lock.
The update adds spellcheck/word replacement options
The new organization tool is folders for holding information. Email features include a unified inbox fro switching between inboxes, organizing messages by threads, and opening attachments in 3rd party apps.
iPhone OS4 includes iBooks to browse, buy, and read books on a mobile device. Users can read books while listening tor music collection. Books can be browsed by title, author, or genre.
Advertisers can opt for media-rich iAds, a potential source of revenue for developers. Developers are given more access to edit events in the Calendar and create SMS messages. Developers can develop apps that for photos and video playing/capture.