Mon Feb 18, 2019 10:18 pm
There are no legal minimum requirements for what instruments you take up - but you’ll doubtless feel you need reliable basic flight instruments.
The iPad’s internal GPS is generally not considered reliable for our purposes, and certainly won’t give you a reliable AI - although it’ll give you the illusion of one.
To do that properly, you need an external box to take pitot/ static input, a fast, reliable GPS, and ideally a gyro for attitude. That’ll transmit it all by WiFi to your iPad, which then becomes an effective EFIS. Examples are the Levil or Telos boxes - or the novel Levil BOM which mounts under a wing, powers itself by airflow, requires no wires at all, and also gives you an AOA indicator.
Depending on the instruments that you’d save yourself, including a compass, you could conclude that this was no more expensive.
For redundancy, you could mount a basic steam gauge or two into the iPad mount itself, so that they’re there if the iPad should go down for some reason, but don’t otherwise use up panel space.
Model of iPad is entirely subjective - might as well go for the largest you can fit in the panel real estate that you’ve freed up from steam gauges, especially if it dual-screens EFIS and moving map. Otherwise a large iPhone or an iPad mini could serve as EFIS, beside a larger iPad for SkyDemon. Buy second-hand.