Frequently asked questions

Here you find answer to the most frequently asked questions about our solution. This page also serves as the basic documentation.

Two steps are necessary to make PhoneX work:

  • First, you need to download PhoneX application from one of the application stores depending on type of mobile device you own. Application is available for all major platforms and you can find it in Google Play, Apple AppStore, and Amazon apps store.
  • Second, you need to create an user account, which you can do directly from the app. After the account creation, we provide you with 7-days trial license for free. When your license expires, your account is in limited mode. To use premium features after the expiration, please purchase a full license at our order page or by contacting us directly.

TCP: 443, 444, 1444, 1443, 3477, 3478, 5060, 5061, 5222, 8442, 8443.
UDP: 3477, 3478, 5060.

Simple answer, no, our solution is not open-sourced. The main reason is our business model and protection of our assets.

Some people claim that open-source mean security but this is a general misconception. From the security perspective, open-source can be reviewed by third-parties, but this does not guarantee security. Take for example OpenSSL project, one of the most important open-source pillars of the Internet infrastructure securing HTTPS connections. Although the library is open-sourced, critical vulnerability Heartbleed was discovered. It was out there for two years so attackers could silently dump private keys from the servers. 

In addition, it is hard to prove that provided binary of open source code - let's say the binary distributed via one of the application stores - is the one built from the source codes that are published. The vendor may insert subtle code changes that may stay hidden in the final application.

Architecture of our system is opened. We publish the way how we do crypto and which algorithms are used.

We are doing our best to keep our solution as secure as possible. Here are several reasons why we believe in our solution:

  • Our advisory board counts experts in the field of cryptography, with years of experience in designing and analysing cryptographic architectures. We have pleasure to discuss our decisions and architecture with such recognized people like professor Vashek Matyáš and Dr. Jaroslav Hrubý.
  • Our developer team has strong security background and years of experience with secure development. Security is not part that can be added to the product, we build our solutions secure from the very beginning.
  • We are EU (Czech Republic) based company. This is a benefit for those not willing to use U.S. based security products.
  • Design of our architecture is public (whitepaper will be published soon).
  • We are using state-of-the-art cryptography algorithms and protocols. We use such well studied algorithms like AES-256 or Diffie-Hellman key establishment. It is out there for years, experts are trying to break it and still no one succeeded.
  • A security audit of our source codes by third party certification authority is a top priority on our ToDo list.
  • We periodically check our source codes with static code analysis tools to reveal potential problems and vulnerabilities. 
  • We perform periodical penetration testing of our system.
  • Before application makes it to the release, it is intensively tested by our QA team.

You can reach us in a traditional way either by phone +420 702 210 210 or by mail at

If you want a more secure way to talk to us you can install our PhoneX application to a mobile device, create a new account and contact us via phonex-support contact you have in your contact list in the application. We are glad to answer your questions about product, pricing, technology, etc... PhoneX support is reachable in business days, from 8:00 to 16:00 CET.

Another way is to use PGP-encrypted email at Our key fingerprint: 4AA8 9C94 8E20 E4D7 83FD 3FEA 0CDB 9578 9429 7951, key is on the public key servers, such as If you don't know how to setup your mail for PGP, we recommend to use Thunderbird mailing client with Enigmail PGP plugin which is very easy to setup and use.

We are very sorry for this situation, but it may happen from time to time. PhoneX application is being tested on multiple devices from various vendors but there are always devices we didn't tested yet. In that case, we would be very grateful for your bug report. 

You can send us your feedback to phonex-support account in your contact list, with description of a bug and your device model. Big thanks for all reports!

We try to react promptly on user bug reports and to release fixed versions as soon as possible.

It depends. You can communicate via PhoneX only with contacts having also PhoneX installed. The another requirement is you have to have the contact added in your contact list and vice versa.

Our solution can be used by individuals but we are mainly business-to-business (B2B) oriented. We aim to provide a way for a secure mobile communication for companies. PhoneX is deployed to organization so it protects communication inside the company (employees) and outside the company (clients). 

You can use either our private-cloud hosted service or choose on-premise deployment package. With on-premise deployment we install PhoneX private-cloud into your infrastructure. We also provide integration with your existing user directories and internal systems you use inside your organization.

Beta testing is a process to ensure quality of our product before we release it to the general audience. To ensure that application is stable and without bugs we release it first to beta testing phase, before it is released to all users. Our beta testers use it as a general user would use it. If some crash happens application automatically sends anonymized crash reports to us so we can fix errors before they reach all users.

You can join our beta tester community to help us with improving our product. On return we give you 1+1 3-month licence for PhoneX as our thanks. Beta tester uses our application just like any other PhoneX user. There are no special requirements for the beta testers. As a beta tester you receive the most up-to-date versions of our products.

Interested? Send us an email to and we will provide you more info.