I am using Damus.  I also downloaded the test flight then as per guideline of one of the nostrian I have to download damus beta. I did not proceed bec the term in damus beta said that I may lost the current info from Damus alone. It also state that I have to do back-up before downloading damus beta.  But how to back-up? 

 I don’t think you’ll lose anything. As long as you have it installed and you’ve backed up your nsec it shouldn’t be a problem. 

 Thanks I will try 

 Once you have the TestFlight running, the last step is to run this script and restart the app. 
https://nostrscript.suhailsaqan.com 

 I have to tap redeem then redeem code is required.  Where will I get it. https://image.nostr.build/f8ad6a1cdb452655e5ac6d701120fb13c0bd2aed149919833d543be70b29a55c.jpg