If I am not mistaken, with this app you can be able to access another wallet from your end which means you can do and undo another wallet with this application. Then from what you have said, is it possible that one can restore a wallet missing phrase with the help of this app. Since the app would be installed in phone and the phone already have the wallet key downloaded in it which sometimes can mix-up, can this app be able to extract the wallet seed phrase from the phone from where is stored displaying it in the sense that the wallet address and seed phrase would be showing at the same time indicating that the both goes together if truly it is the same phone or device that was used in installing the wallet via the seed phrase.

If it is possible then OP, you have rendered a bid solution to missing wallet key phrase. Many would key into your product just to restore their old wallets holding funds.

I don't believe I misunderstood, but you are actually selling a mobile wallet app with the help of which whoever buys it will be able to scam someone else? So person A buys the app, puts the link somewhere and waits for person B to download the app and make a transaction in the wallet that person A will then empty?