Thanks for the response.
I can use steemconnect easily on my mobile phone, and login with a single click almost. Thought Hivesigner would be just as easy.
It looks like Hivesigner detects I am viewing the page on a mobile phone. It redirects me to some sort of import page and request a Hive username with a password or key. I cannot find any other options to set up a new Hivesigner password or import an account any other way. Maybe it was never intended for mobile use?
With Hivesigner you have to import the account with the key, then set a password each time you use a different device or browser.