iTeleport has released an update to its VNC remote control application for iPhone and iPad devices, introducing support for iOS 4 Fast App Switching and the iPhone 4 Retina display. iTeleport 4.0.4 is available from the App Store for $25 and is a free update for current users.
Toodledo has updated its iPhone task management app to provide support for iOS 4 Fast App Switching and background synchronization when exiting.
Toodledo 2.0.1 also provides support for the iPhone 4 Retina display, fixes a problem with the rotation lock on iOS 4 and improves French and Italian translations. Toodledo 2.0.1 is available from the App Store for $4 and is a free update for current users.
Urbanspoon has released an update adding Fast App Switching for multitasking-capable iOS 4 devices.
There appear to be no other notable changes beyond iOS 4 support. Urbanspoon is available from the App Store as a free download.
Amazon has updated its Kindle app with optimizations for the iPhone 4 Retina display, but oddly does not appear to have added support for other new iOS 4 enhancements such as Fast App Switching.