This tool lets you edit any messages sent and received, including contact number, message time, and message body.
Simple and easy to use, download to find more.
====Note for below the comments
Some users feedback that certain messages can not be edited, I think problem is not they can't be edited, but they do not get loaded, for such case, please load the messages with correct phone number, sometimes it might carry a different phone number even it is in the conversation.
keyword: sms, edit, editor, tool
v 1.5 - fix app not working on android 4.4 kitkat devices