CKalender vs Da Buzzer
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
CKalender
Manage and view appointments in an online group calendar directly from your smartphone or tablet. Requires an existing account with app activation for full functionality.
- View group calendar appointments
- Manage appointments
- Smartphone and tablet compatibility
- Online group calendar integration
Read full descriptionHide full description
CKalender ist eine App zur Anzeige und Pflege von Terminen im Online-Gruppenkalender v1.ckalender.de per Smartphone oder Tablet. Zur Nutzung ist ein bestehender CKalender-Account mit App-Freischaltung notwendig.
Da Buzzer
This app allows you to know when visitors arrive without installing hardware. Generate a unique QR code that guests scan to send you an instant notification. It's ideal for homes and businesses, supporting multiple users and working anywhere with internet access.
- QR code powered doorbell
- Instant visitor notifications
- No hardware or batteries required
- Supports multiple users
- Works anywhere with internet
- Customizable visitor pages
Read full descriptionHide full description
Your Doorbell, Reinvented. Da Buzzer is a smart, wireless, and effortless way to know when someone is at your door—without installing hardware or relying on batteries. Simply generate and print your unique QR code. When guests scan it, you instantly receive a notification on your phone. Perfect for Every Home or Business Whether you live with family, share a space with roommates, or manage a storefront, Da Buzzer supports multiple users. Add several people to the same QR code so everyone gets notified at the same time—never miss a visitor again. Always On. Always Reliable. No wires. No power source. No extra devices. Da Buzzer works anywhere you have internet access, making it ideal for buildings with limited infrastructure or frequent power outages. Create a Personalized Welcome Customize your QR-powered visitor page with names, instructions, or location details—helping guests know exactly where to go and who they’re there to see. Da Buzzer turns any door into a smart entrance—with zero setup hassles.
Screenshots
Verdict
The clearest difference is review sentiment: Da Buzzer at 80% against CKalender's 0%. Da Buzzer also leads on in-app purchases (none vs 1). CKalender's advantage is update cadence (every 4 months vs every 15 months) and iOS requirement (11.0 vs 17.0). On price, ads, monetization model and device support there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Both are free to download. CKalender sells 1 one-off in-app purchase. Da Buzzer asks for nothing beyond the download.
CKalender ships an update every 4 months, Da Buzzer every 15 months. The most recent releases landed on October 13, 2026 and September 23, 2026 respectively.
| Parameter | CKalender | Da Buzzer |
|---|---|---|
| Price | Free | Free |
| Rating | — | 5.0 (6 ratings) — better |
| Positive reviews | 0.0% of reviews | 80.0% of reviews — better |
| Number of ratings | — | 6 — better |
| Update frequency | Every 4 months — better | Every 15 months |
| Ads | No | No |
| In-app purchases | Yes | No — better |
| Monetization | Free | Free |
| Devices | iPhone, iPad, iPod — better | iPhone, iPad |
| Requires iOS | 11.0 — better | 17.0 |
| Further details — not scored | ||
| Size | 3 MB | 12 MB |
| Age rating | 4+ | 4+ |
| Developer | Reinhard Hanselmann | Rahul Rahate |
Customer experience
CKalender
Da Buzzer
In-app purchases
CKalender
- CKApp-Freischaltung$2.99
Da Buzzer
No in-app purchases
