Apple has postponed the announced date when all Mac App Store applications must be sandboxed, from November 2011 to March 2012. Maybe that's because sandboxing isn't working either for Apple or for developers. Developer Wil Shipley ruminates on why requiring application sandboxing is the wrong strategy for Apple.

Earlier, we referred you to a blog post by Marco Arment showing that iOS 5 could delete the contents of an app’s caches folder and temporary folder behind the app’s back, thus leaving the app with no safe place to store data. Now, MacRumors reports that the release notes for the beta of iOS 5.0.1 say that it “introduces a new way for developers to specify files that should remain on device, even in low storage situations.” This should fix the problem Marco described. iOS 5 will also bring back multitasking gestures to the original iPad, and is said to address the infamous battery life issue.

Marco Arment, developer of Instapaper, explains why iOS 5 could mess up Instapaper and many other apps. If an app stores a lot of data in Documents, Apple now slaps its hand because Documents can be backed up by iCloud; but if an app stores a lot of data in Caches, iOS 5 can now delete that data at will. So any app that moves its data store from Documents to Caches can lose that data. Apple argues that this is okay because Caches is for data that can be reconstructed — say, by re-downloading it from the Internet. But what if the deletion happens while offline? Someone with a Wi-Fi-only device could store stuff just before leaving the house, only to find it gone later. And, as Marco points out, Apple deletes the data but the app developer receives the hate mail.

Over at Macworld, Andy Ihnatko ponders whether Lion’s sandboxing feature might mean that one of Apple’s best babies — interapplication communication — is being thrown out with the bathwater. Notice also the link to a Jason Snell article in a parallel vein. This is something that some of us here at TidBITS have been quietly worrying about for months.

With each new major Mac OS X revision, we eagerly look forward to reading John Siracusa’s in-depth discussion in Ars Technica, and this time is no exception. The description is full, the opinions are spot-on, and the technical information is fascinating.

Matt Neuburg and Chuck Joiner talk you through Lion’s new features in this MacVoices podcast. The takeaway message: remain calm.

Following on from his TidBITS article about finding your PowerPC applications in case Lion won’t run them, Matt Neuburg talks to Chuck Joiner on MacVoices about the possible loss of Rosetta in its historical context, and what it might mean for users.

Chuck Joiner hosts a wide-ranging MacJury discussion, surveying the iPad’s past and considering its future, with a panel including TidBITS’s own Matt Neuburg.

Matt Neuburg has been writing a book about iOS programming, entirely in good old-fashioned unformatted plain text — and loving it. He describes his workflow in this short essay.