Every time you type a meeting title into Google Calendar, you are handing over a surprisingly intimate part of your life to a company whose business model relies on profiling you. Your calendar reveals where you work, who you meet, how often you visit the doctor, and what you do on the weekends. If this access falls into the wrong hands, it can cause a lot of damage.
Google Calendar is not end-to-end encrypted, which means Google holds the keys to all of your data. You could switch to some shockingly efficient text-based calendars to protect your privacy, but you give up the cross-platform sync that makes Google Calendar so easy to use. Thankfully, there’s a privacy-focused alternative, and the sync still works.
Fossify Calendar is one of the best open-source options
A clean, no-nonsense calendar without tracking
Fossify is a community-maintained fork of the old Simple Mobile Tools suite, resurrected after the originals went closed-source and started pouring in ads. The calendar app is exactly what you’d expect: lightweight, open-source, with no ads, analytics, or unnecessary permissions.
Open it, and you get the usual calendar view rather than a nudge into some smart assistant flow. You can flip between month, week, and day views, search for events, and add new ones with a single tap. Recurring events such as reminders and all-day entries are all there. It also supports multiple calendars, local storage, and the standard Android event provider, so it works well with whatever is on your Android phone.
Visually speaking, you get themes, dark mode, and home-screen widgets that make sense. All of that, while the app collects no data, doesn’t try to link your schedule to an advertising profile, and it is perfectly happy living entirely offline if that’s what you want.
- OS
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Android
- Price model
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Free, Open-source
A clean, open-source calendar app that keeps your events local and free from tracking.
DAVx5 is the missing piece
The secret behind cross-device syncing
Fossify Calendar on its own is great if you are fine with a single device. However, if you want to sync your calendar to a desktop or another phone, you’re going to need a sync provider. This is where DAVx5 comes in.
DAVx5 is an open-source CalDAV/CardDAV sync adapter for Android. CalDAV is the open standard for calendar sync that projects like Nextcloud, Fastmail, and many self-hosted groupware servers use. It doesn’t sync with Fossify directly; instead, it syncs with Android’s system calendar storage. Fossify and any other calendar app on the device simply reads from and writes to that shared store.
This approach has two major benefits. First, you’re not locked to a single app. If you ever decide Fossify isn’t for you, your events stay on the same system, and another can read them instantly. Second, you can choose any CalDAV server, regardless of whether it’s a self-hosted Nextcloud instance or a small VPS running a minimalist CalDAV server.
One thing to keep in mind is that while DAVx5 is available on both the Google Play Store and F-Droid, the Play Store version requires a one-time payment to download the app. If you don’t want to pay, you can download the same app from F-Droid for free.
- OS
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Android
- Price model
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Free, Open-source
An open-source sync adapter that connects your calendar and contacts to any CalDAV/CardDAV server across devices.
Setting up doesn’t require a weekend
Install an app, punch in credentials, and you’re good to go
Setting up DAVx5 is boring in the best possible way. You install the app, grant it calendar permissions, and tap the plus button to add an account. If you’re using a hosted CalDAV service, you paste in the server URL and login credentials, and DAVx5 will automatically discover all available calendars.
Services like Nextcloud or even Google allow you to log in with your credentials right away and sync your calendars. So even if people at your office use Google Calendar, you can synchronize those events to Fossify and any other calendars you might be using seamlessly.
On the mobile side, follow these steps to sync your calendars with Fossify Calendar:
- Open your calendar and press the settings gear icon in the top right.
- Scroll down and enable the CalDAV sync toggle.
- Select the calendars you want to sync and tap OK.
And that’s it. All your calendar events with any other calendars synced with DAVx5 will instantly appear in Fossify Calendar.
Desktop syncs work more or less the same. You point your calendar client at the same CalDAV server, and DAVx5 takes care of the rest. No Google account, no proprietary magic, just a well-implemented open protocol doing its job.
My calendar stays in sync across every device I use
Android, desktop, and beyond
The obvious question with a setup like this would be reliability. Google Calendar has trained people to expect near-instant updates, and anything less feels broken.
Once configured, your DAVx5 instance can come quite close to this, depending on what you prefer. You can tune the sync interval, force a manual refresh, or, if you’re using compatible servers like Nextcloud, enable push changes so that updates show up almost immediately. It’s a digital calendar setup that can actually keep you organized without overwhelming you with options and appointments from dozens of different calendars.
From Fossify’s perspective, it’s simply reading from Android’s calendar database. If DAVx5 has pulled down an event, it shows up. If you create an event in Fossify, it goes into that same database and then out to the server on the next sync.
Privacy-focused, but actually usable for once
For once, a privacy-focused alternative doesn’t require you to give up convenience
This setup isn’t a perfect clone of Google Calendar, and requires some setting up to work as intended. You won’t get automatic suggestions across your whole organization, or one-click Meet links injected into calendar events. If your job or organization relies on Google Workspace, this is not quite a drop-in replacement. Sure, Google Calendar has some genius tricks up its sleeve, but the data collection is just too much.
This underrated calendar app with perfect sync makes Google Calendar feel ancient
I didn’t expect a calendar app to wow me, but this one genuinely transformed my workflow.
That said, for personal scheduling, side projects, shared family calendars, and even reading your work calendar, it’s perfectly adequate. What you lose in Google’s fine-tuned interfaces, you gain in control. More importantly, your calendar stops being an input stream into a global advertising machine.
