Google Vision Android SDK
I was looking into possibilities for me to use the Google Vision API however I needed to know how well protected it was before I did so.
Alas I ended up finding a MITM vulnerability that allows people to pretend to be a certain app as far as Google is concerned which basically means they can use your API keys for free and you get to pay for them.
I ended up not going through with whatever project I was thinking could benefit from the Google Vision API.