How do you install the Arduino IDE on the Raspberry Pi running an ARM version of Ubuntu or Raspbian? There doesn't seem to be any official ARM release. Both distros have an "arduino" package in their standard repos, but it only includes an ancient 1.0 version that's missing a lot of features.
Arduino at http://playground.arduino.cc/Linux/Raspbian recommends:
sudo apt-get update && sudo apt-get install arduino
but indeed warns that the version is old:
Note: This will install an old version of Arduino, and may not support some of the newer boards. You can not download a newer version from the website, because there is no ARM version. -- Arduino wiki on Raspbian
Looking at the raspbian respository at http://archive.raspbian.org/raspbian/pool/main/a/arduino/ currently lists 1.0.5
There are folks working newer versions of Arduino for ARM at https://github.com/arduino/Arduino/issues/3334 but it isn't finished yet.