How secure is compiled Desktop App?

[AlbertoD]

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.app .exe security question

If I compile an encryptionKey into my app, is there any way it can be opened with a text editor or otherwise hacked and find the key value. I know would be an arduous tasks, but is it possible. I have tried to open both the .app package and then try to open the components unsuccessfully. But how secure is compiling a password into the code?

safe password storing in compiled app

I have user name and password for web service that app connect to. If I open compiled app with HexEdit I can find user name and password in plain text. What would be best way to hide this 2 parameters?

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