I understand your concerns. But let me clarify that this is a secure service. All sensitive information is stored encrypted, all traffic runs entirely over encrypted SSL and all goes through Plaid Technologies, one of the most prominent service provider of banking data. If you would like some more info, you should check: https://plaid.com/security/
Well, the service is intended for people who don't do it manually. People who are lazy about their finance.
And the goal is for them to get automatically an email every week or month with basic information about:
— How much did they spent or win last month?
— How much savings do they have in all their bank accounts?
— How did their finances progressed in the last months?
— How much do they normally spend each month?
— For how long could they live with their current savings?
About having an API. You should check: plaid.com. That's the API service I am using on sssaving.com to get all data.
I agree. But probably banks will never get into that business.
Meanwhile some companies, like the one I am using for this service, are helping the banks to get this functionality. You should check them: http://www.plaid.com.