Tool comparison
Kalender Sync vs. Fantastical – beautiful app meets real sync
Fantastical shows all your calendars beautifully in one app – and that's exactly where the misunderstanding lives: an app view is not a sync. Your colleagues, your booking tool and the free/busy lookup in the company Outlook never see Fantastical. They see the providers behind it – and there, your calendars stay separate. Here's an honest look at what makes Fantastical strong and why Kalender Sync is more companion than replacement.
Background
What can Fantastical do?
Fantastical by Flexibits has been the premium calendar app in the Apple ecosystem for years – for Mac, iPhone, iPad, Apple Watch, Vision Pro and now Windows too. It connects Google, Microsoft 365, Exchange, iCloud, Todoist and CalDAV in one interface, and shines with natural-language input, "Calendar Sets" (quickly switchable calendar groups, e.g. work vs. private) and the "Openings" scheduling feature. The free tier is a solid basic app; Flexibits Premium costs $56.99/year (or $6.99/month), the family plan $89.99/year – each with a 14-day trial. The key point: Fantastical is a display and input layer. It reads your calendar accounts but doesn't copy events between providers.
Strengths
Where Fantastical is strong
Possibly the best calendar app, full stop
Natural-language input ("Lunch with Anna Tuesday 12pm"), thoughtful design, weather, time zones, templates – as a daily driver on Apple devices, Fantastical is hard to beat.
Calendar Sets for context switching
Switch between "Work", "Private" or "Side project" with one click – each group shows only the relevant calendars. For your own overview inside the app, it's brilliantly done.
Openings for simple scheduling
Share availability as a link, with slots automatically blocked based on your existing events – a solid scheduling feature built right into the app.
Where Kalender Sync wins
Where Kalender Sync makes the difference
An app view is not a provider sync
Calendar Sets organise what you see – they change nothing about what's actually stored in the calendar accounts. Your private iCloud event still doesn't exist for your company's M365 tenant. Kalender Sync works one level deeper and genuinely writes events as "Busy" into the other providers – so the truth is right everywhere, not just in your app.
Visible to everyone who doesn't use your app
Colleagues checking your free/busy times in the company Outlook, booking tools verifying availability, the assistant scheduling meetings: they all look at the provider, not at Fantastical. Without real sync, they offer slots you've long since filled. Kalender Sync closes exactly that gap – invisibly in the background, while you keep using Fantastical up front.
Three visibility levels per sync
Per synchronisation you choose: "Busy" only, "Title + time" or full details – with a custom display name for blocked slots. Your private life blocks your work calendar without giving anything away.
Two-way sync and live-sharing into other calendars
Changes flow in both directions, and by invitation you can embed your availability live into another person's calendar – as real events, not an ICS subscription. No calendar app can do that, however beautiful it is.
GMX, WEB.DE and the full provider range
Kalender Sync connects 9 provider types – including the German consumer providers GMX and WEB.DE, which regularly get left out of Apple-centric setups. iCal feeds and Infomaniak kSuite are on board directly, too.
GDPR, German hosting, DPA
Flexibits is a US company. Kalender Sync is GDPR- and BDSG-compliant, hosts at Hetzner in Nuremberg and offers a DPA for business customers – relevant as soon as client or employee data lives in the calendar.
Considerably cheaper – with a permanently free start
Flexibits Premium costs $56.99 a year. Kalender Sync starts with a permanently free plan (one synchronisation), Basic costs €4/month, Business €10/month – with a 14-day Business trial, no credit card. Combine both and the sync layer costs less than the app.
Decision guide
When should you pick which?
You use Fantastical (and keep it) if:
- You live in the Apple ecosystem and want the best calendar experience.
- You mainly want to view and manage your calendars yourself – that's what the app is built for.
- Natural-language input, Calendar Sets and design genuinely ease your daily routine.
Kalender Sync joins the stack if:
- Others see your availability wrong – colleagues, booking tools and free/busy lookups check the providers, not your app.
- Events should genuinely arrive in other calendar accounts – as "Busy", "Title + time" or full details, chosen per sync.
- You need two-way sync and live-sharing into other people's calendars, not just a pretty unified view.
- You want the broadest provider coverage in this comparison: 9 provider types – Google, Microsoft Outlook/M365, Apple iCloud, GMX, WEB.DE, mailbox.org, Infomaniak kSuite, CalDAV and iCal feeds. Kalender Sync is the only tool in this comparison that connects the German providers GMX & WEB.DE.
- GDPR, German hosting and a DPA are non-negotiable for you.
Keep your favourite app – Kalender Sync works invisibly behind it
Fantastical displays your calendars, Kalender Sync keeps them in sync at provider level – GDPR-compliant, hosted in Germany, from €0.
Try free for 14 daysCurrently supported providers
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