Google Fi, launched back in 2015, is an MVNO telecom service by Google, providing calls, SMS, and data services through networks operated by T-Mobile and US Cellular in the USA. It has a few headline features that separate it from the rest of the crowd, but it's more or less just another mobile network. However, one unique feature that Google is now rolling out is end-to-end encryption for phone calls to other Fi users. End-to-end encryption ensures that conversations stay encrypted from when they leave your smartphone, to when they arrive at the other end. There is no server-side decryption, meaning that data can’t be collected in the middle from the servers that pass your messages along.

End-to-end encryption is a selling point of many texting applications like Signal as it’s a major step towards ensuring the privacy of a user, and Google is one of the first to offer it in phone calls. The company says that SMS messages sent on the network still aren't end-to-end encrypted, but encourages users to check out Google Messages, which has end-to-end encryption when using Rich Communication Services (RCS). Users will be able to see if they're on an end-to-end encrypted call from the Dialer, but they will also hear a unique ringing tone before being connected, too. Phone calls over normal carriers

Calls will be end-to-end encrypted by default, though there are some limitations. It requires a cellular or Wi-Fi connection, and it will not work with non-phone devices, such as a computer. It won't work for group calls with more than three participants either, and call details such as duration, phone numbers, time, and voicemails are not encrypted. There is no option to disable end-to-end encryption either, and it will automatically be enabled so long as you and the other person are both on Android smartphones on Fi.