This phone, which I assume is not too different than the E5: * ships with openssh (not enabled by default). * ships with the phablet user account as a sudoer * has a terminal app in the Ubuntu App Store * BQ publishes all their source on their github repo
You will need to change the rootfs to rw or else apt-get fails. This breaks the OS image diff update mechanism. It comes with the ubuntu-touch repo, which is accessed via the standard dpkg apt-get and aptitude tools. Strangely, there is no git in this repo, which I built from source. Ships with a standard toolchain in the repo also. From this I was able to compile nmap and other tools I needed.
The OS is in its very early days. Overall its a great platform and hope that it becomes a major player. It won't replace my iphone just yet (it lacks any kind of block based encryption to protect the phone contents).