If most cryptographers and one prominent NSA whistle-blower are to be believed, Signal by Open Whisper Systems – branded TextSecure on Android before it recently got merged with RedPhone – is the most secure traditional messaging app in use today – that is, not counting those that require Tor, the Bitcoin blockchain or other tech out of the reach of regular users.
I am pleased to say that a TextSecure compatible client for the Ubuntu phone has been in the store for a while, and today it is stable enough to be used regularly. The basics are all working – end-to-end encrypted texts and group chats, photo, audio, video and contact attachments.
Note that this is not a replacement for the standard messaging app as it does not send or handle SMS.
On first run you will be prompted for your phone number, will need to manually confirm the received SMS verification code, then asked to import your address book contacts to see which of them is already using Signal.
There are still enough bugs lurking and major features missing – encrypted message store, push notifications that require server side work, support for multiple devices synced with the same phone, even encrypted phone calls, which aside from the large amount of work involved may or may not be possible depending on what the Ubuntu phone SDK exposes.
While new features are being added it is very likely that backwards incompatible changes will be introduced to the way message storage is handled, and while attempts will be made to make migration painless, do not yet store any important information solely in the application’s database.
Both the conversation SQLite database and the attachments are under /home/phablet/.local/share/textsecure.jani in case you need to access them independently of the app.
The project is written entirely in Go. Working with Go for the backend library and with go-qml for the UI has been a mainly positive experience, although I wish go-qml were more actively maintained and had a more complete coverage of the common APIs and use cases that C++ Qt/QML developers are used to.
Jani Monoses: TextSecure for the Ubuntu phone
Source: Planet Ubuntu