here is a quick demo of how to set your ubuntu touch device up to use tethering on vivid. 
once you have run the following commands and rebooted you will find hotspot in your settings- mobile section.
as root, so use sudo -s 1) add-apt-repository ppa:ci-train-ppa-service/landing-046 2) vi /etc/apt/preferences.d/silo.pref Package: * Pin: release o=LP-PPA-ci-train-ppa-service-landing-046 Pin-Priority: 1002 3) apt-get update 4) apt-get install indicator-network qml-module-ubuntu-connectivity libconnectivity-qt1 ubuntu-system-settings libsystemsettings1 at this moment, this installs: indicator-network 0.5.2+15.04.20150722-0ubuntu1 qml-module-ubuntu-connectivity:armhf 0.5.2+15.04.20150722-0ubuntu1 libconnectivity-qt1:armhf 0.5.2+15.04.20150722-0ubuntu1 ubuntu-system-settings 0.3+15.04.20150723-0ubuntu1 libsystemsettings1:armhf 0.3+15.04.20150723-0ubuntu1 5) reboot After that, the menu shows up.