Update - All Clear
Sept 17, 2013 - FileMaker has released an update for FileMaker Go (12.0.8) which fixes the Get ( PersistentID ) for iOS7. (Notes of FileMaker's release are here.) This means that folks using the latest FileMaker Go and GoZync 4x have the all-clear to upgrade to iOS7. Folks using previous version of GoZync still need to update to GoZync 4 as described below.
What changed in iOS7?
In iOS7 two FileMaker functions will perform differently than they do now:
Get ( SystemNICAddress ) will fail.
Get ( PersistentID ) will return the same value for all devices.
This means that if you're using these functions for mission critical aspects of your solution you'll need to retool or postpone upgrading to iOS7 until there is a fix from FileMaker.
Is GoZync Affected: what should I do now?
1. If you're using a version of GoZync prior to version 4, you must update to version 4 of GoZync as soon as possible. Version 4 does NOT use these functions for mission critical operations. This is a free update and instructions are here: upgrade instructions. Prior versions will fail under iOS7 and will not work even after FileMaker releases a patch to FileMaker Go even now that FileMaker has released a new version of Go.
2. Even if you're on version 4, Do not upgrade to iOS7 until we've given you the all-clear on this page. We're hoping that FileMaker addresses this issue quickly. Read on to learn what exactly happens to GoZync 4 under iOS7, but the short answer is that it would be best for you to postpone upgrading until FileMaker releases a patch for FileMaker Go. FileMaker has released a patch for Go and all you need to do is this...
3.1 Tell all your users to upgrade to the latest version of FMGo in their IOS App Store.
3.2 Log into GoZync License as an administrator and delete all the devices. You may need to do this a few times if your users don’t all upgrade to the latest Go at once. Reason for this is that the new version of FMGO will give everyone new device IDs and the OLD device IDs are already taking up your licensed devices, so you'll need to clear them out.
3.3 You should both of these things even if your users aren't moving to iOS7 right away. These changes work in iOS6 and will have you ready for iOS7.
Background
The two functions affected (especially Get ( PersistentID )) are used to uniquely identify iOS devices. Some developers who roll their own sync or don't use UUIDs may even use these functions as part of syncing data itself. All these things will likely break in iOS7 until FileMaker releases a patch.
GoZync Version 4 and higher.
GoZync 4 does NOT use these functions for syncing itself.
GoZync 4 uses Get ( PersistentID ) for logging, so if you do upgrade to iOS7, all of your users will have the same log entry. Not the end of the world, as it doesn't affect the sync, but not ideal.
GoZync 4 also uses Persistent ID for licensing, so if you upgrade to iOS7, all your devices will get a new ID. This means that you'll likely be told you're exceeding your licenses when you next connect: simply delete all the earlier devices to make room for your new ones. If you haven't managed/ deleted devices in GoZync before, you'll find instructions here:
ManagingDevices.
Update. Now that FileMaker has released a new version of Go that fixes Persistent ID, the only issue for GoZync users is that they'll get new persistent IDs. This means you'll want to log into GoZync License and delete all the earlier devices to make room for your new ones: you'll find instructions
here.
Earlier versions of GoZync
Earlier versions use Get ( SystemNICAddress ) as part of Field Level Merge and elsewhere. These versions will not sync correctly under iOS7 and should NOT be used.
If you absolutely can't update to GoZync 4, please
get in touch and we can see if there is a remedy short of updating available, depending on how you're using sync. The most important thing is to make sure your users
do NOT update to iOS7 until you have brought your code up to date.