I believe simple login is a part of proton and that it’s included in certain proton plans… it’s actually really difficult to find for certain, but I think if you buy a proton plan that has “pass plus” it includes simple login: https://proton.me/blog/pass-plus-simplelogin-premium-feature

Hope that helps, just FYI one of the slightly irritating features is not being able to search email body only title etc on the web mail. But other than that it’s been pretty good

Unusable unfortunately since they don’t support anything other than US date format or currency.