Earlier quoted context omitted.
I recently got a free Android phone, and would also never let it near anything that could extract money from me, and am conscious of the information it can disclose. Sorry, legitimate Android app developers! I would like to pay you for the things you create, but your neighborhood is too sketchy for me to visit.
That's pretty ridiculous, we're talking about credit card purchases here, which can be trivially charged back, not bitcoin private keys... if you've worked with sensitive info on a Windows box though, that's probably a much worse off environment.
Using a smartphone for banking is really dangerous because banks often use a phone as a second factor and compromising the phone gives full access to your bank account. And many phones do not get security updates.