If you are reading this, it means that you are looking to buy the most secure encrypted phone available in the market. Well, the best ones are always the ones that are not entirely "commercial" , and that are usually sold to armies and intelligence agencies, all over the World.
Every system can be hacked, bear this in mind. Never forget this fact: all encrypted phones connected to the service provider's servers, they are totally unsecure and extremely " hackable".
Another important fact to consider is that all encrypted phones that are running on the cellular network, even if they have an 'anonymous' SIM card, they are easily intercepted.
Yes, more important facts and please make no mistakes about it: ask yourself who is creating the encryption keys and for you and where they are stored?
Usually commercial providers of so called "encrypted phones", are the ones that are managing your own encryption keys, and for us this is nonsense. Really ? Are you absolutely sure that you want to give the keys to your most guarded secrets to third parties? Do not be such an idiot .... whoever created those keys for you, can access them and decipher your data, either directly on the 'encrypted phone' he sold you or through their servers.
So what is the ultimate solution? First of all a communication system that is not channeling the encrypted conversations on any server. Second it must be based , on encrypted internet connections , at least , and not present on the cellular network. Third is the encryption keys ....this is the key to any data you really want to make sure that it will never, ever, leak out from your systems.
As long as you are not the generator and sole manager of your encryption keys , you will always be exposed to hacking, interception and surveillance.