Semaphor combines the best features of collaboration apps and encrypted messaging apps. Your team can work together through team messages, direct messages, and file sharing. Semaphor is secured by the power of private blockchain and end-to-end encryption.

Semaphor brings you and your team:

› End-to-end encryption to protect every file and conversation
› Fast file uploads
› Secure file sharing
› Private direct messaging
› Unlimited, project-specific channels
› Real-time communication and collaboration
› Password-less account creation
› Native offline mode
› Mobile and desktop friendly
› Enterprise and LDAP ready
› Supports bots and integrations
› Reviewable source code

To find out more about Semaphor, visit our website or send us an email. We always welcome your feedback and suggestions.


- Basic: Free 30-day conversation history
- Standard: Unlimited conversation history and access to Standard channels. $8.99/month
- Pro: Unlimited conversation history and access to Pro channels. Team admin pays for all team members. $8.99/user/month
- Payments will be charged to iTunes Account at confirmation of purchase.
- Subscription automatically renews unless auto-renew is turned off at least 24-hours before the end of the current period.
- Your account will be charged for renewal within 24-hours prior to the end of the current period, and identify the cost of the renewal.
- Subscriptions may be managed by you and auto-renewal may be turned off by going to the your Account Settings after purchase.

By installing this app you agree to SpiderOak's:

Privacy Policy,
Term of Use,
Service Agreement,

What’s New

Version 2.2.0

This version of Semaphor improves on the updated look that we rolled out in April and continues to bring new features and fixes from our development team. Our teams have been working tirelessly to not only implement changes you asked for, but to find better ways to execute the features you already enjoyed.
Your feedback, suggestions, and reports make a huge difference to our team. Please don’t ever hesitate to reach out to us through, @SpiderOak on Twitter or on Facebook at

## New Features:

- Add notice for data storage
- Updated styling
- Removed URIs
- Update device OS/version identification code
- Upload all file types from Android

## Bug Fixes:

- Fixed Android attachment error
- Fixed back-button Android corner cases
- Mobile rendering improvements
- Large screen improvements
- Channel switcher improvements
- Channel search improvements
- Fixed channel selection error when adding team members
- Fixed multiple activation in team/channel creation
- Fixed broken channel view after leaving team
- Team switcher improvements
- Fixed avatar change not working
- Fixed input context menu not appearing when spellcheck is unavailable
- Dialog improvements
- Autocomplete improvements\
- Fixed devices sort order
- Fixed About dialogue
- Scrolling improvements
- Fixed code injection in Markdown URL parsing
- Fixed HTML injection in editor mention tag
- Added page reload mitigation for desktop
- Confirmation code improvements
- Update Electron to disable its executable stack
- Adjusted pattern matching so that display names will be highlighted in a message even when it’s adjacent to a non-word character

Ratings and Reviews

4.0 out of 5
7 Ratings
7 Ratings
lip16 ,

Great security, mediocre everything else

I appreciate that Semaphor provides a much more private and secure alternative to Slack. But its user experience is inferior to Slack in every way; and that makes it harder to use and harder to persuade others to use, and thus makes its security and privacy benefits illusory.

erewhon76 ,

iPhone X Support Required

Why this update would not include iPhone X display support? Waited long enough for an update.

WebThingy ,

Could be great, but...

I'm a fan of all things SpiderOak, but Semaphor is a bit of a tease. If the notifications worked and you didn't have to constantly scroll down to read new messages between two users it would be awesome. Other than those two issues it's great, but if I don't get notifications then what is the point? If you leave the app open they usually come through, but no notifications at all if it's closed.


SpiderOak, Inc.
20.2 MB
Requires iOS 10.0 or later. Compatible with iPhone 5s, iPhone 6, iPhone 6 Plus, iPhone 6s, iPhone 6s Plus, iPhone SE, iPhone 7, iPhone 7 Plus, iPhone 8, iPhone 8 Plus, iPhone X, iPhone XS, iPhone XS Max, iPhone XR, iPad Air, iPad Air Wi-Fi + Cellular, iPad mini 2, iPad mini 2 Wi-Fi + Cellular, iPad Air 2, iPad Air 2 Wi-Fi + Cellular, iPad mini 3, iPad mini 3 Wi-Fi + Cellular, iPad mini 4, iPad mini 4 Wi-Fi + Cellular, 12.9-inch iPad Pro, 12.9-inch iPad Pro Wi-Fi + Cellular, 9.7-inch iPad Pro, 9.7-inch iPad Pro Wi-Fi + Cellular, iPad (5th generation), iPad Wi-Fi + Cellular (5th generation), 12.9-inch iPad Pro (2nd generation), 12.9-inch iPad Pro Wi‑Fi + Cellular (2nd generation), 10.5-inch iPad Pro, 10.5-inch iPad Pro Wi‑Fi + Cellular, iPad (6th generation), iPad Wi-Fi + Cellular (6th generation), iPad Pro (11-inch), iPad Pro (11-inch), iPad Pro (12.9-inch) (3rd generation), iPad Pro (12.9-inch) (3rd generation), and iPod touch.
Age Rating
Rated 4+
© SpiderOak, Inc.
In-App Purchases
  1. Personal Plan Monthly $8.99


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.

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