Doesn't support the most basic functions
I really wanted to like N26 and to be able to use it as my primary account but it's just not possible.

It doesn't support the most basic banking functions which I would expect on any bank account (this is all for UK accounts as of 2019-06-03):
* Direct debit is not supported
* No overdraft
* No standing orders
* Cannot save recipient details: This shocked me. It's such an easy feature to add. When I send money to a friend I expect it to be able to remember the contact details so I can use them again in the future.

Finally the big selling point for me was that they supposedly had a fully functional website which I could use to send money and view my transaction history (most challenger banks for some reason don't have this). It turns out this isn't completely true. To send a transaction you still need to confirm on your phone which makes it quite pointless since the reason I want a website is for when I don't have access to my phone.

To end on a positive note: The set up was fast and easy and the support is good. Their app looks pretty as well (although feature wise it could also use quite a bit of improvement).

I will look at N26 again next year and I hope they have fixed all of these issues. If they have then I will gladly give them another try. Oh well, back to a traditional bank for now it seems :(

EDIT: Reply to N26

When I contacted your support I was told that direct debit was not supported (about a month ago). Well I guess that's one less thing stopping me from using N26.

As for the security of paired devices; a phone is not necessary more secure than a computer. Most banks are fine with using a computer without the phone, I see no reason why N26 should be any different. Also if you want extra security you could use a standard like OTP (e.g. with Google Authenticator) that way it is up to the customers if they want to have the app installed on their phone and if they want to have the OTP credentials on other devices like their computers.