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Results of the Year. Thank You!

2016 was an important year for SFLetter.com in terms of implementation and deployment of new features. And not without your help! We considered all your feedback and suggestions, so we can safely say that our service is developed completely based on your desires and needs.

Today we want to look back and see why and for whom we created this service, how it evolved, and what we have achieved together with you within a short period of time.

Technologies for people

Why was SFLetter.com created?

Internet users have begun to think seriously about the protection of personal information in the network, especially after a series of break-ins to accounts of celebrities and officials, as well as the leakage of user account data from various company servers (SONY, Skype and others.) So we decided to create a service that would meet the requirements for protection of personal information sent to the network for all users, both private and corporate.

For individuals we offer protection of personal correspondence and pictures.

For business and government - protection of commercial secrets, top secret emails and confidential documents.

For internet publishers - protection against forwarding emails and documents to third parties and copyright infringement.

For freelancers, consultants, designers and everyone who maintains a private practice - protection of original work, designs, drawings, models and others, from unscrupulous clients.

Inside the service

It was not enough to only ensure good protection of documents and emails- from the outset we also tried to give users the maximum amount of technology to make the service easy to use.

Special non-standard file format

As we know, all information sent over the internet is scanned and analyzed. Google, for example, does it in order to provide targeted advertising for users. Facebook does the same. Files in SFPDF format cannot be scanned and analyzed in any way. This, ensures the highest level of privacy for correspondence

1 user = 1 device

Using SFLetter, only the intended recipient can open a protected email message on his device, without any possibility to open it on another device or to forward it to another user.

Access control

You can instantly revoke access to already sent email messages, for example in case an incorrect recipient's address was used, or set a timer that automatically blocks access to the letter after a certain period of time.


Tracking lets you know the date when a message was read, the recipient's IP-address, and information about any attempts to forward the message.

We hope that you like this feature set that is available absolutely free of charge to all users.

Professional recognition and awards

In 2014, we received a nomination for the Runet Awards. A year later Droider.ru added SFLetter.com to the list of four Russian innovative projects of the year. And in the last part of the year we were in the finals of Digital Summit, the First National IT Awards.

Despite the fact that SFLetter.com is only two and a half years old, the number of registered users from different countries and continents is now over 13 000. This makes the service in demand on the global internet.

The results of our common efforts

This year we have implemented a lot of new functionality. Let's look what we've achieved thanks to your ideas.

Mobile apps

Initially, we only had one program for viewing protected messages and attachments on Windows devices. Now we also have readers for Android, iOS ,and macOS.


We have introduced support for IMAP and SMTP for your convenience to use SFLetter.com with any mail client and on any device.

Domain name

Now you can put your own domain name in the sender email address. Details.

Protected bulk emails

Now you can send protected bulk emails to your clients, colleagues or friends. Details.

Plans for the future

We have a lot of unrealized ideas that we want to turn into reality for you to make the service even more easy to use, interesting and effective.

Thank you for being with us!

Yours SFLetter.com