[Xamarin] securing/obfuscating connection strings and passwords

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C#

Xamarin

I'm wondering how to best obfuscate connection strings and passwords in Xamarin.

I am connecting to a Cosmos DB and the connection string is retrievable from the .apk files, (dotfuscator don't do a good enough job).

I'm new to this kind of security measures, as I've worked on internal software using data that hasn't required it. Now I'm working on an app containing person details real-time and historical location data, so I'm hysterical about the service being hacked

Thanks for any and all help and and input

What I have tried:

Googling, only to get information about https and obfuscating of actual code