Don't know how about others, but Mistertango have electronic money institution license issued by central bank of Lithuania
https://www.lb.lt/en/frd/view_license?id=412But it's not a full bank. I'm not sure, they report to government institutions or not, but if they will get request to do that - they will provide all information about you that they have.
I'd say EMI is even better than bank, 'cause EMI's licence does not let you lend the money. So, all the money people deposit to their Mistertango account is always there and is supervised by the Bank of Lithuania.