Posteo is my second choice alongside Mailfence to possibly replace ProtonMail because of issues with the Android apps outlined here. Like Mailfence, Posteo, based in Germany, is more of a mini-office service with calendar, notes and contacts modules. The first thing that has to be said about Posteo is that it has to be one of the greenest and ethical companies operating in the tech arena. The company is powered with electricity from Green Planet Energy, all staff are employed on full contracts and even have a subsidised vegetarian lunch menu. However, what is important is the lengths the company goes to regarding security and encryption.