Facebook is such a useful and popular social media app that you can keep the connection with your friends and families, share important moment in your life, find more friends with ease. During the process you use Facebook, you may have saved huge numbers of messages through which you can always think back what happens at that time. However, due to many reasons you may want to delete these Facebook Messenger messages on your iOS device. For example, maybe you just want to free up more space for other files, delete messages that are useless any more or erase messages that are troublesome. However, you may delete emails by mistake. What's more, you may find these deleted messages quite useful in the future. As you find in the Facebook app, there are two options: Delete and Archive, when you decide to erase messages. Please note that there is a big difference between the two options – through Archive, your removed messages will disappear on the checklist while you can still get access to them in the future; by choosing Delete one, your messages will be deleted forever.