Is it possible to get the IP-address of the wireless connection on a mobile device with Ubuntu touch even when it's not connected via USB?
you can connect your device to pc throught with USB.
you can read [this website][https://wiki.ubuntu.com/Touch/ReleaseNotes#SshAccess], a paragraph about Accessing the devcie over ssh
An easy way is to scan your network with nmap...
First of all:
Depending on your network ip and subnet setup use nmap to scan:
The above will scan all ip's from 10.0.0.0 - 10.0.0.255
edit: If you like GUI's you can also install zenmap