Howdy ,
Thank you for reporting this issue. I have tested out this issue and have been able to place a particle system into my level, deploy it to an iPhone 6 plus, and see the particle system without any errors being present. Would you be able to clarify what asset you were using exactly when you were testing this issue?
I was using the P_electricity_arc.uasset. I did notice that if you go directly behind the particle system you are able to see errors. Here is what i currently see:
One is showing fine as long as you are in front but the other is producing an error when behind it.
Any additional information would be greatly appreciated.
Thanks and have a great day!