Adding another voice to this. I am another of the multiple-paid-accounts group. I'm in the Apple ecosystem so that's my focus but this should be everywhere.

Please give us multi-account login. I have more than one (paid) Proton account and I can't log into all of them simultaneously via the OSX Proton Mail app. Mail is my first pain point but I need this in all your products.

This is super critical - especially for those who use/want to use Proton for business and personal - would also love to be able to log into multiple accounts for all the other proton apps both on mobile and desktop (MacOS). Need to be able to get to drive for business and drive for personal. Would like to be able to all all proton accounts to native Mac OS apps as well.

Need account switching between personal and business accounts too in MacOS proton app.

How is this not getting more attention?

We need the ability to log into multiple calendars simultaneously on mobile!

Skiff sunsets on August 19 and we need Proton to have this capability by then!

The ability to switch between user accounts on Desktop Mail and Cal app would be useful (to me at least).

Besides my private account I share one account with my wife for mutual mailing and calendar functionality.

Functionality to switch accounts like in the web browser is what we need! :-)

In short: the ability to switch between accounts without logging on-and-off all the time.

I have multiple paid Proton Mail Accounts. I recently started using the Proton Mail application for Linux. There should be a easy switch option between accounts. At the moment I can only sign in on 1 account at a time

Logging into multiple accounts on the mail app is great. I would also love to be able to log into multiple accounts for all the other proton apps both on mobile and desktop.

Absolutely this is needed.
you can log in to multiple email accounts via the android mobile app, but you can't log into more than one account with the calendar app.

With the demise of Skiff, people who want to move secondary accounts over to Proton may not in the end, as you can't log in to a second calendar in the app.

Please implement it!

Yes, this is essential when you want to separate Work and Private accounts. I really hope this will be a possibility soon!

The thing that makes me want this feature is the following:
I have 2 accounts for which I want to see the calendar. This can be achieved by sharing the calendar of one account with the other and have edit rights.

But if I want to invite someone with the other account for an event, I cannot do that. It makes sense, as an email should be sent with the other account and I only have the rights to the calendar.

Being able to log in to both accounts in the calendar app would resolve this issue.

I am in the process of setting up over 100 Proton Family Accounts this would be extremely useful for these clients to be able to switch accounts like they can in Protonmail now. Thank You

Yes, it's the same thing, it's the brake that keeps me from switching to full proton.

I need to have a unified view of my business and personal accounts.
Likewise, if I could switch email accounts more easily via a tab.

It would be great to have this for the same reason as Mark: separating a private and business account. With the lack of multiple accounts in the calendar app I'm now forced to share the calendars between the accounts to see all of them in the app.

I was surprised this wasn't a thing as well. Separating Private and Business is pretty common and crucial. I have both my business and private in Proton.

I've solved it now by subscribing, but this won't allow me to create appointments, so that's pretty cumbersome.

+1 vote for an Account Switcher in the Calendar app, to prevent sharing via a URL and to have appointment creation a first-class citizen

This is not the same thing as sharing a calendar for edit.

Assume someone has two proton accounts, one for work and one for personal. It would be helpful to be able to view these calendars without logging out of one account and logging into the other. The mail app allows for two users logged in, I'm not sure why the calendar app can't do the same thing.

Sharing a calendar for edit would achieve the same function, but I imaging it could be a bit more complex in terms of authenticating the user. And the current implementation of sharing, passing a URL around, seems fraught with security issues. Allowing multiple users, like the current mail app seems far more secure.

+1

should be treated in this topic https://protonmail.uservoice.com/forums/932842-proton-calendar/suggestions/42282604-sharing-a-calendar

The ProtonMail mobile app (Android in my case) allows to have 2 email accounts logged in. This allows having a personal email account and a shared email account with my wife. We can easily switch from one to the other.

In the ProtonCalendar mobile app, it would be nice to support showing the calendars from 2 accounts, at the same time in the same calendar view.

This would allow sharing a calendar with other people easily, both using the same shared email account.