I did that flight with the a350 with my iPad (7th generation) in high settings with very high airplane count
I use the iPhone XR, with full graphics, the only thing I do is to select low power mode in settings, oh and the brightness low, if you have issues with the low power mode, just tell me
IPad mini 4.
Graphics all on Low. When I landed I put them to Medium (even though I always do flights on medium-high, I chose Low to reduce the risk of the game crashing)
I do low to medium generally and nothing happens
It depends on your device. If you use a phone or a small tablet for long haul, be sure to play it safe by reducing the amount of battery usage in order to reduce the chances of crashing. However, if you own a decent tablet, then I’d say it’s safe to run at least medium graphics. Obviously it’s still best to play it safe, but if you’re confident in your devices abilities, then you can run long haul flights on higher parameters. I’ve been running 18-22hr flights on medium-high graphics, no battery saving mode and every other parameter pretty much set to normal with an iPad Air and there’s no problem of crashing for me, so it does come down to the device you’re using and the precautions you take.
I have a descent device and before the update as able to run max graphics prior to the update but on my SIN-EWR flight it crashed with in the last hour.
Some precautions you can take are to restart your device before every flight, clearing cache, use a low battery mode, making sure your device is close to your router and to make sure you’re not running any other app than IF during the duration of the flight.
Basically I’ve not done any of those except restart the device and I was able to pull of a longer flight
To play it safe you should try to carry out those precautions, but in most cases a simple restart does prevent crashing most times.