# EteSync — Secure Data Sync > Secure and open-source data synchronization for contacts, calendars, and tasks. (iPhone/iPad app by EteSync Ltd.) - Source: https://appshunter.io/ios/app/etesync/id1489574285 (this page in markdown: same URL + `.md`) - Developer: [EteSync Ltd](https://appshunter.io/developer/1489574284) - Category: Productivity, Utilities - Price: Free - Rating: 3.05/5 from 20 App Store ratings · 14 written reviews indexed - Age rating: 4+ - Requires: iOS 10.0 · 45 MB - Languages: English - Released: 2019-12-19 - Data updated: 2026-08-10 - Monetization: free - User reviews in markdown: https://appshunter.io/ios/app/etesync/id1489574285/reviews.md ## What is EteSync? EteSync is a secure and privacy respecting sync for contacts, calendars and tasks. With this application you can sync your EteSync data with your iOS device! In order to use this application you need to have an EteSync account, either on an existing server or your own (it's free and open source). Easy to Use =========== EteSync is very easy to use, you just put in your credentials and the app is ready to use. Secure & Open ============ EteSync is secure and respects your privacy. Don't believe us? You shouldn't, just verify yourself, both the client and server are open source. Full History ========= A full history of your data is saved in a change journal which means your data is never lost, even if deleted, and you can always restore, revert and access past versions of your data. ## Key features - Secure data synchronization - Contacts, calendars, and tasks sync - Privacy-respecting - Open-source client and server - Full data history and restore - Easy to use setup ## Recent user reviews (10 of 14) All indexed reviews: https://appshunter.io/ios/app/etesync/id1489574285/reviews.md ### 1/5 — Love the idea *2025-07-08* But it doesn’t work. I ran into a million problems like needing to reinstall the app after getting rid of all my previous contacts sources and needing to sign up on the web because the app has no affordance for that. And empty contact list initialization failing. I finally gave up after repeatedly ending up at “cipher text cannot be decrypted using that key”. ### 1/5 — Sadly, just doesn't work *2025-06-29, version 1.6.1* I went through the setup, but then the app just gives an error when connecting. I'll look elsewhere for a solution. ### 1/5 — Doesn’t work *2024-04-09* This seems like an awesome service but just keep getting an error when trying to set it up. ### 1/5 — Hasn’t been updated in nearly 3 years *2023-12-02* Please add some basic features something like automatic syncing via shortcuts should be a bare minimum for this app. ### 1/5 — Great idea, but doesn’t work well with iPhone in my case *2023-10-07* It’s a really great idea and I wish it worked well with iphone. Unfortunately, in my case, since synching with iphone I have contacts disappearing and some events on my iphone calendar broke the sync with my desktop app. E.g. a contact I used just yesterday disappeared and there’s no trace of a change in the app changes log. Reinstalling and starting fresh new contact lists doesn’t solve all the problems. I reported the problem but it’s very difficult to characterize when these things happen so difficult to reproduce. It’s 5++ stars for what they’re trying to do, but it least in my experience it’s not there yet. ### 4/5 — Only one issue so far, otherwise it works *2023-10-04* The setup is bit odd, but that is mostly because of Apple’s restrictions and other nonsense. Once setup, it works but I hav one issue: it doesn’t auto sync for some reason. ### 1/5 — Good on android, disaster on iOS *2023-08-07* The app works well on Android, but tried on my Wife’s iPhone and it is terrible. Constantly crashing, does not work well with calendar or contacts. It is completely useless. ### 3/5 — Love the Concept, Just Couldn’t Get It To Work *2023-07-25* This is exactly what I’ve been looking for to sync my contacts and reminders privately without having to have to use iCloud and feed Apple all of my personal data. I just couldn’t get it to work after many hours of trial and error to successfully sync. Perhaps some updates and it will work flawlessly and I will certainly come back to try again and very willing to pay to have the service work swimmingly to sync E2E between my devices. Love the concept! ### 2/5 — 😞 *2023-07-18, version 1.6.1* It doesn’t work. At first I had some error messages and then uninstalled it now a few days later I thought I’ll try again and now it doesn’t get passed the login screen. I’ve notice the app hasn’t been updated in two years which explains the problem possibly. Love this to work though. Anyone know of any alternatives? 1 star for my disappointment but another star because I’d love this to work. :) ### 3/5 — Great idea, but doesn’t work well with iPhone in my case *2022-04-29, version 1.6.1* It’s a really great idea and I wish it worked well with iphone. Unfortunately, in my case, since synching with iphone I have contacts disappearing and some events on my iphone calendar broke the sync with my desktop app. E.g. a contact I used just yesterday disappeared and there’s no trace of a change in the app changes log. Reinstalling and starting fresh new contact lists doesn’t solve all the problems. I reported the problem but it’s very difficult to characterize when these things happen so difficult to reproduce. It’s 5++ stars for what they’re trying to do, but it least in my experience it’s not there yet. ## Frequently asked questions about EteSync ### What is EteSync? EteSync is a secure and privacy-respecting synchronization service for contacts, calendars, and tasks. It allows you to sync your data across your devices using open-source clients and servers. ### Does EteSync have ads? No, EteSync is ad-free. The application does not contain any advertisements, ensuring a clean and uninterrupted user experience. ### What devices does EteSync support? EteSync is available for iOS devices, including iPhone, iPad, and iPod. It is designed to work seamlessly across these platforms. ### How often is EteSync updated? The latest version of EteSync is 1.6.1, which was last updated on October 16, 2020. Update frequency can vary based on development cycles. ### What is the age rating for EteSync? EteSync has an age rating of 4+. This indicates it is suitable for users of all ages, with no mature content. ### Can I restore deleted data with EteSync? Yes, EteSync saves a full history of your data in a change journal. This means your data is never truly lost, and you can always restore or access past versions. ### Is EteSync free to use? Yes, EteSync is free to use. You can create an EteSync account on an existing server or host your own for free. ### How does EteSync compare to other sync services? EteSync emphasizes security and privacy with its open-source nature and full data history features, differentiating it from many proprietary sync solutions. ## Version history (last 5 releases) ### 1.6.1 — 2020-10-16 * Bug fixes and improvements ### 1.5.2 — 2020-09-20 * Improved protocol compatibility * Speed ups ### 1.4.2 — 2020-09-15 Improved protocol compatibility ### 1.3.5 — 2020-04-23 Improved accessibility ### 1.3.4 — 2020-03-31 * Fix handling of events that moved across calendars. * Made some errors fetching events and reminders non-fatal * Gracefully handle token expiration * Many more fixes and improvements ## Apps similar to EteSync | App | Rating | Price | Category | | --- | --- | --- | --- | | [Thetis Tools](https://appshunter.io/ios/app/thetis-tools/id1460268980) | — | Free | Productivity | | [SyncOnSet 5.0](https://appshunter.io/ios/app/synconset-50/id1460160860) | 1.8 (60) | Free | Productivity | | [Your Ashford BC](https://appshunter.io/ios/app/your-ashford-bc/id1452979480) | — | Free | Productivity | | [Jumpstash](https://appshunter.io/ios/app/jumpstash/id1465670860) | 4.2 (5) | Free | Productivity | | [OneTwoCount](https://appshunter.io/ios/app/onetwocount/id1454584180) | — | Free | Productivity | | [ZappID](https://appshunter.io/ios/app/zappid/id1455029820) | — | Free | Productivity | ## More apps by EteSync Ltd - [EteSync Notes](https://appshunter.io/ios/app/etesync-notes/id1533806351) All apps by EteSync Ltd: https://appshunter.io/developer/1489574284 ## Related topics [etesync](https://appshunter.io/ios/topics/etesync) · [resync](https://appshunter.io/ios/topics/resync) --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-10.*