Is there a privacy sensitive/aware calendar service for individuals (not business)?

I'm not keen on the idea of hackers and/or corporations and/or government knowing about my personal and embarrassing medical appointments. So, I'm looking for a Google Calendar alternative that has a very compact and straightforward privacy policy, and hopefully is outside of the US (where I live). I also need the ability to sync with iOS (very important) and, if possible, android (less important). Also, it would be great if its 3 dollars or less per month. I've done some searches with DuckDuckGo, StartPage, IxQuick and even Google and have only been able to find Fruux so far, on this page. It's free but it's privacy policy isn't exactly ideal.

Any suggestions are appreciated.

 

I think Smartphones and other "app based" platforms have built-in support for managing calendars/events. So instead of a calendar app privately maintaining its own calendar data, it would normally use platform APIs (such as EventKit on IOS, Calendar Provider on Android, ...) to store and manipulate that data. Thus calendar data is exposed to, and easily accessible to, the platform/OS and also any other apps that are allowed to access calendar data. Which is fine, even useful in various ways, as long as the platform software and (other) apps with calendar access aren't doing something and/or aren't vulnerable to something that would put your calendar data at risk. IOW, don't overlook the client-side threats and any "features" that might send your calendar data elsewhere

Many calendar programs work with iCalendar files (https://en.wikipedia.org/wiki/ICalendar) which can be privately synced or synced/shared through an intermediary *in encrypted form*. This approach would seem best suited to contexts where calendar manipulation is being done by the fewest number of users.

I think CalDAV (https://en.wikipedia.org/wiki/CalDAV) remains the most widely supported means of storing/syncing calendar data through a "proper" calendar-aware server and in such a scenario the server *will* have access to the calendar data. You may not be interested in or have the time to do this, but since privacy is your objective I will point out the possibility of setting up your own server. A fully private one in your own home, or if deemed acceptable, a VPS or other type of server rented from a privacy/security oriented web hosting company.

http://caldav.calconnect.org/implementations/servers.html

 

I don't know if it syncs with iOS, but I think Zoho probably includes a calendar in their online office suite and are better for privacy than Google. Of course, having it well secured from hackers and the NSA is probably another story. Countermail has a calendar in their webmail system. That's probably as secure as you're going to get with an online calendar. But I suspect it doesn't sync with iOS.

I kind of think that unless someone is specifically making a secure calendar app for iOS or Android, that by the time you sync any online calendar with your phone, you've probably pretty much given up the game. Phones OSes are just a nightmare for security and privacy. I would assume that any built in app in iOS or Android is tracking everything you do with it.