It's not against their TOS for me as a customer to reverse engineer their mobile clients (AFAIK), it is against their TOS for you as a bank customer to give Tel

It's not against their TOS for me as a customer to reverse engineer their mobile clients (AFAIK), it is against their TOS for you as a bank customer to give Teller any authentication details. This is nothing new, the incumbent aggregator Yodlee also causes users to violate the bank TOS in this way. But aggregators solve such a pain point that users are prepared to use these services. Every UK bank is aware of Teller, even ones I have not interacted with directly. I've been up to Edinburgh and to the RBS London offices a bunch of times, I know them well. I hope to work with the banks and not against them.