I have iOS 5 beta installed on both iPhone 4 and iPad 2. After using them for several hours (minus iMessage, which isn't yet active), I think these app categories are royally screwed. Camera: Camera replacement apps. I like and will use Camera+ still (particularly for stabilization, clarity filter, and timer), but lock screen access to built-in Camera app means it will be used a lot less. These apps will now have to compete against Photos app for processing and sharing photos. iMessage: Free texting apps, especially those that do not offer SMS or Google Voice. Some users will undoubtedly continue to use them still, but many will lose a large chunk of the user base. Reading List: Instapaper and Read It Later. I love Instapaper, which happens to be the first iOS app I purchased. But since I don't use its social feature, unless developer adds something major (e.g., voice reading), I don't see myself using it. Reminders: Basic "to do" app category (e.g., Appigo's Todo, Toodledo, Wunderlist). Power GTD apps (e.g., OmniFocus, Things) are probably unaffected, however. That said, just as there are countless weather and stock apps, good and fairly priced replacement apps will continue to thrive. But Apple has done an excellent job with these 4 apps/features. I suspect many will simply fade away.