Comparison

Synctrain vs Sealed Letter

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Synctrain

Securely synchronize files and folders between your devices. Stream audio and video directly from other devices. Manage file sharing permissions to control access to your data.

Highlights
  • Secure file synchronization
  • Full folder synchronization
  • Specific file selection
  • Audio and video streaming
  • Cross-device file mirroring
  • Customizable sharing permissions
Features
Read full description

With Synctrain you can securely synchronize files with other devices that have Syncthing installed. You can choose to synchronize full folders, or choose specific files. With Synctrain you can also stream audio and video files from other devices. When you synchronize files, all changes, including deleting files, also happen on your other devices. Do not use Synctrain for back-up purposes, and always keep a back-up of your data. You decide with which devices you share which files. This also means the app makers cannot help you access or recover any lost files. This app is powered by Syncthing. This app is however not associated with or endorsed by Syncthing nor its developers. Please do not expect support from the Syncthing developers. Instead, contact the maker of this app if you have questions.

About

Sealed Letter

Features
Read full description

Write messages now. Share them in the future. Sealed Letter is a private and thoughtful way to write messages, letters, instructions, or important information today, then choose when and how they can be accessed later. It is designed for words that deserve care, privacy, and the right timing. Instead of sending a message immediately, you can prepare it in advance, keep it sealed, and decide who should receive it, when it should become available, and how it can be opened. Whether you’re writing something heartfelt, practical, or important, Sealed Letter helps you stay in control until the moment is right. What you can do with Sealed Letter Write future messages: Create meaningful letters, personal notes, guidance, or important instructions that can be delivered or accessed at a later time. Seal letters until they’re ready: Keep your message private until the access conditions you choose are met. Choose how letters are shared: Let a letter be picked up securely with letter details and a password, or deliver it directly via email or inside the app to a chosen recipient. Schedule access for later: Letters are not available immediately unless you choose them to be. You decide when a letter can become available in the future. Assign trusted people: Choose trusted contacts who can receive letters or help release them when needed. You decide their role and level of access. Stay in control: Your letters remain private and controlled by you. Nothing is shared unless you explicitly choose how and when it should be shared. Intentional by design: Sealed Letter is not a chat app or social network. There are no feeds, public profiles, comments, or replies. It is a quiet space for messages that deserve time and care. Simple and calm experience: Clear language, minimal distractions, and a gentle interface help you focus on what matters most. Sealed Letter gives you a peaceful way to prepare meaningful messages for the future, so the right words can reach the right person at the right time. Privacy Policy: https://www.sealedletter.co/privacy/ Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

Synctrain4 screens
Sealed Letter4 screens

Verdict

The call

The clearest difference is in-app purchases: Synctrain at none against Sealed Letter's 2. Sealed Letter's advantage is update cadence (fortnightly vs every 6 weeks) and iOS requirement (15.0.0 vs 17.0). On price, ads 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

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Sealed Letter sells 2 in-app purchases, starting at $0.99 per month. Synctrain asks for nothing beyond the download.

UpkeepUpdate frequency

Synctrain ships an update every 6 weeks, Sealed Letter fortnightly. Both last shipped on October 24, 2026.

Scorecard3 real differences · 7 level
Synctrain versus Sealed Letter: the parameters behind the verdict, then further details
ParameterSynctrainSealed Letter
PriceFreeFree
Rating4.9 (142 ratings) — better—
Positive reviews89.5% of reviews—
Number of ratings142 — better—
Update frequencyEvery 6 weeksFortnightly — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree—
DevicesiPhone, iPad, MaciPhone, iPad, iPod
Requires iOS17.015.0.0 — better
Further details — not scored
Size33 MB30 MB
Age rating4+4+
DeveloperT-ShapedContinuia OU

Bugs and requests

Synctrain

Reported bugs

2 issues
  • Occasional app crashes
  • Sync delays on some devices

Requested features

2 requests
  • Direct photo/video sync to remote devices
  • Faster initial connection to server

Sealed Letter

Not enough reviews yet to summarise bugs or requests.

In-app purchases

None

Synctrain

No in-app purchases

2 purchases

Sealed Letter

Subscriptions2
  • Sealed Letter Subscription$0.991 Month
  • Sealed Letter Subscription$9.991 Year

Questions

Is Synctrain free?
Synctrain is free to download, with no in-app purchases.
Is Sealed Letter free?
Sealed Letter is free to download, with in-app purchases available.
Do Synctrain or Sealed Letter have ads?
Neither Synctrain nor Sealed Letter shows ads.
Which is updated more often, Synctrain or Sealed Letter?
Synctrain ships an update every 6 weeks, and Sealed Letter fortnightly. Most recently, Synctrain was updated on October 24, 2026 and Sealed Letter on October 24, 2026.

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