All in a sudden, my message app in iOS 9.3.1 started crashing … after, surfing apple’s official site, I found that this bug, which has been discovered on May 29, 2016, crashes Messages app due to a specific set of unicode string characters are received on the recipient’s device. I was trying all different methods, however did have luck. This is because, I received few other valid sms after that particular unicoded sms. Thus, while i was using Siri, Siri was sending messages to a valid sender instead of the unicoded sms sender. Therefore, I was required to identify the sender of the unicoded sms initially. Lucky, I have iMazing installed in my mac, which helped me to access all the messages individually and to identify the sender’s number of the unicoded sms. i imitated the following steps and managed to solve the issue.
1. Launched the Settings app from my iPhone
2. Tapped to Notifications
3. Tapped on Messages
4. Toggled Show on Lock Screen to Off.
5. Connected my iPhone with the mac and took a latest backup using iTune.
6. Opened the iMaze application on Mac and checked the Messages
7. Identified from which number I received the unicoded sms.
8. launched Photos from my iPhone
9. Selected any Photo and tapped on the Share button
10. Tapped the Messages icon
11. Enter the number of the sms sender and sent the message … Bingo … Message App is now running smoothly …