On Thursday night, Apple published a support document, acknowledging that the company is aware of the iMessage bug causing Apple devices to respring or reboot. The document includes a temporary fix and states that a software update will be published soon to fix this issue.
The issue, also known as Effective Power, is caused by the way Unicode decodes characters. Resulting in a memory overload, causing the device to respring or reboot. The issue goes a step further for many users, as the bug restricts certain users form being able to open Messages.app on their devices.
Apple is aware of an iMessage issue caused by a specific series of unicode characters and we will make a fix available in a software update. Until the update is available, you can use these steps to re-open the Messages app.
According to Apple, to temporarily fix this issue follow these steps:
Step 1: Invoke Siri by either pressing and holding the home button or saying “Hey Siri” when your device is plugged in. Once Siri is present, ask Siri to, “read my unread messages.”
Step 2: Siri will attempt to read the message. (Though, it is impossible to read unicode in English.) Siri will then ask you if you would like to reply, say yes.
Step 3: It doesn’t matter what you say. The part that matters is the message being sent.
Step 4: Once the message is sent. You should then be able to open your messages app as normal. You then want to delete the entire thread containing the Effective Power message, or you may go into the thread, tap and hold the Effective Power message, tap more and then delete the message.
The document states that this only a temporary fix and that a software update will be pushed out soon (presumably iOS 8.3.1 or iOS 8.4, which is still in beta stages).