How-to: Install Ubuntu SDK in Ubuntu 12.04 64Bit

Step-by-step:

1. Install Qt 5 via Ubuntu PPA

sudo add-apt-repository ppa:canonical-qt5-edgers/qt5-proper

2. Install the Ubuntu SDK Preview

sudo add-apt-repository ppa:ubuntu-sdk-team/ppa && sudo apt-get update && sudo apt-get install ubuntu-sdk notepad-qml

If you got the problem as like the following:
The following packages have unmet dependencies: ubuntu-sdk : Depends: ubuntu-qtcreator-qt5libs but it is not going to be installed Depends: ubuntu-qtcreator-plugins but it is not going to be installed E: Unable to correct problems, you have held broken packages.

Try to install the android-adb-tools via this ppa
sudo add-apt-repository ppa:phablet-team/tools
sudo apt-get install phablet-tools android-tools-adb android-tools-fastboot

3. If you still got like the following,

E: /var/cache/apt/archives/qtchooser_0.0.1~git20121229.g8f08405-0ubuntu1~precise1~test5_amd64.deb: trying to overwrite ‘/usr/bin/qdbusxml2cpp’, which is also in package libqt4-dev

Then, try this one to solve the problem
sudo dpkg –force all -i /var/cache/apt/archives/qtchooser_0.0.1~git20121229.g8f08405-0ubuntu1~precise1~test5_amd64.deb sudo apt-get -f install

4. Get started to make Ubuntu apps like in here.

Ubuntu SDK interface via Qt Creator

Sources:

1. developer.ubuntu.com
2. https://wiki.ubuntu.com/Touch/Install?action=show&redirect=TouchInstallProcess
3. http://askubuntu.com/questions/259319/ubuntu-sdk-does-not-install-on-ubuntu-12-04-64bit