Here's my profile graphs while using iPad-mini 1st gen. for tests:
[attachment=1:2jl3vs21][/attachment:2jl3vs21]
The spike at the end is when a new scene is loaded (physics and collision present) and crashes.
And below is the test using the simulator. The simulator won't crash, but you can see an increase of system load. Notice, the lower gap in the graphs are due to a second scene with just a few resource.
[attachment=0:2jl3vs21][/attachment:2jl3vs21]