Tech: Everything you need to know about iPhone OS version 4.0
- good The new iPhone OS supports multitasking (whoo!), in-app ads, unified inboxes and multiplayer games.
- bad The update doesn’t
work on all iPhones, and multitasking doesn’t work on the still-for-sale iPhone 3G. - worse One thing pushed in under the radar was an effective block of Adobe’s Flash-to-iPhone compiler. source