What about when 99pc of the banks will only offer iOS and Android.

No or os will be able to compete with them because the backing apps don't work.

Now OSes can stagnate and become worse because they know you'll sick to them because you have no choice.

A new player would need to create a OS and a bank to compete. And probably more stuff.

So we're in agreement then that they would've lost the freedom to bank electronically using any computer and software of their choosing.