As Dom said, we get issued with our own set of Jepps that we must update and carry, i.e. a load of bits of paper that weigh a tonne. We have the JeppFD-Pro app on our iPads but at the moment we are not allowed to use our iPads on the flight deck once the flight deck door is closed. We have conducted groundschool 'training' on the use of the app and have 'trained' on it in the sim but we now wait for the JCAB to approve a trial for use in the aircraft, as we obviously cannot use the evidence of other states because the FAA etc clearly cannot be trusted to do these things correctly
During the trial we will still have to carry, and keep updated, the paper Jepps. Hopefully the trial will be a success and we will then be allowed to be like normal pilots and carry just the iPad (and enjoy the bonfire of Jepp paper). The trial will be a trial because it not only has to convince the JCAB that we won't blow up because we've turned on an electronic device on the flight deck but we also have to convince the Japanese pilots that it is possible to read and use charts that aren't covered in multi-coloured highlights
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