Excenter
01No Center
Excenter has no central server that stores your messages. Your messages and contacts are kept on your own device.
02No Watcher
Messages and calls with friends are encrypted. Even the service operator cannot read their contents.
Content sent to in-app Support or submitted in a report is reviewed by the operator so we can respond and improve the service. Responses may be provided by AI. Privacy policy ↗
Why auxiliary servers are still needed
When a friend is offline, an auxiliary service temporarily holds encrypted messages and discards them after 30 days. It cannot read their contents. Auxiliary servers also help with relaying, registration checks and incoming notifications through Apple.
More checks.Less room for abuse.
Phone number verification, checks for a genuine iPhone and app, and one account per iPhone work together to make impersonation and throwaway accounts harder.
- Verify your phone number
- Check the device and app
- One account per iPhone
- Friends by mutual agreement
What we have tested
On October 26, 2026, we tested adding friends and sending messages between devices in a Linux Wi-Fi environment with no internet access.
This was a Linux test. It does not establish that offline calling works on actual iPhones.
Generated images illustrate the ideas behind Excenter. They do not show real users or a specific competing service.
Features
Free messages and calls
Text messages, voice calls and video calls between Excenter users are free.
Offline? Your message can wait.
If your friend is offline, your message shows “Not sent.” It is delivered automatically when they come back online. No need to send it again.
Bring the group together
Create groups of up to 100 people, with up to 6 people on a group call.
Friends by mutual agreement
Scan a QR code or invite someone from your contacts. You become friends when both of you agree. Add up to 5,000 friends.
Send more than words
Share photos up to 10 MB, files up to 20 MB and voice messages up to 60 seconds long.
Share your everyday moments
Post photos and updates for your friends in Moments.
Moving to a new iPhone? Scan a code.
Use your new iPhone to scan the QR code on your current device and transfer your account.
Report or block unwanted contact
Report unwanted behavior or add someone to your blacklist.
Do more with mini apps
Mini apps bring additional features to Excenter. The first is UTEL, a phone service.
Three languages. Your choice.
Switch between English, Japanese and Chinese in the app’s settings.
Get started
Install Excenter
The iPhone version is not yet on the App Store. Once it is released, search for Excenter and install it.
Create your account
Tap “Sign Up” and enter your country and phone number. Follow the instructions to call the number shown, with caller ID turned on. The call ends immediately and is free. Enter your name to finish. You don’t need a password.
Add a friend
Tap “Scan” to read a friend’s QR code, or send an SMS invitation from your contacts. You can start talking once your friend accepts.
Start a conversation
Choose a friend to send a message. You can also start a voice or video call from the chat screen.
Switch to a new iPhone
On your new iPhone, tap “Transfer from another iPhone” and scan the QR code on your current device.
Set up UTEL
UTEL requires a separate application and identity verification. Scan the QR code you receive, then open UTEL in the Discover tab to make calls.
Help
Can someone I don’t know message or call me?
No. On Excenter, only friends you have approved can contact you. Dedicated UTEL numbers are an exception: they can be shared publicly for work and can receive calls from people outside your friends list.
Will I be charged for the verification call?
No. The call ends immediately. Make sure caller ID is turned on; we can’t verify a hidden number.
Why does it say “This iPhone is already registered with another number”?
Each iPhone can have one account. If you haven’t registered before, for example if you bought a used iPhone, email Support. We’ll check and help you register again.
What if I forget my password or get a new phone?
Excenter doesn’t use passwords. On your new iPhone, tap “Transfer from another iPhone” and scan the QR code on your current device. Contact Support if your old device is no longer usable.
Why does my message say “Not sent”?
Your friend is offline. Your message will arrive automatically when they come back online, so you don’t need to resend it.
Can I take back a message I’ve sent?
You can recall a message within 2 minutes of sending it. After that, you can delete your own copy, but it will remain visible to the recipient.
How many friends can I add, and how big can a group be?
You can have up to 5,000 friends. Groups can include up to 100 people, and group calls support up to 6 people.
Why can’t I send a photo or file?
Check the size first. Photos can be up to 10 MB and files up to 20 MB.
How do I report unwanted behavior?
Open the chat info screen and tap “Report” at the bottom. Choose a reason and the relevant messages, then submit your report. You can also add the person to your blacklist.
Can Excenter read my conversations?
The operator cannot read the content of your messages or calls with friends. Content you send to Support or submit in a report is reviewed by the operator to respond and improve the service, including responses provided by AI.
Is Excenter available on Android or desktop?
Not yet. Those versions are being prepared, and no release date has been announced.
How can I use UTEL?
You need to apply separately and complete the identity verification required by law. UTEL does not support emergency calls, including Japan’s 110 and 119 numbers.
How do I delete my account?
Go to Settings → Account and security → Delete account.
What should I do if I see an error?
If your friend hasn’t accepted your request, wait for them to approve it. You can’t message or call someone on your blacklist. If the country code isn’t recognized, enter your number with a country code such as +81.
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