Collecting antiques is getting harder but not impossible when it involves smartphone and tablet apps. Apple and Google are limiting the availability of apps that have gone too long without an update – but the two companies aren't being equally strict about it. For now, each allows a workaround.

Apple announced April 29 that it would consider an app neglected if it had “not been updated within the last three years” and had “not been downloaded at all or extremely few times during a rolling 12-month period.”

Meeting both criteria would lead to the app’s developer getting a warning of the app’s possible removal from the App Store – which, since that’s the only practical way to distribute an iPhone or iPad app, amounts to a death sentence. Developers have up to 90 days to ship an update to lift that threat.

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This policy represents a retreat from an earlier rule that Apple had revealed through emails to developers this spring: Two years without an update would make an app subject to removal, with only 30 days to ship an update.

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In either case, users with the app already installed should be safe. “Your app will remain fully functional for current users,” Apple’s policy reads – including support for in-app purchases. And backing up an old iPhone or iPad device and then restoring that backup to a new phone or tablet should move the app over.

Many developers remain unamused by this policy.

“This is another reminder that Apple controls all distribution of iOS apps, which means that these rules, and any others, can leave developers and users without choice,” emailed Brent Simmons, developer of NetNewsWire and other apps.

Apple declined to comment on the record but confirmed that outside of titles removed for being malware, an app no longer available in the App Store will transfer to new devices via the backup-and-restore process.