iOS app crashes, xcode says 'Lost connection to X's iPhone' when debugging

Solution 1:

Just chipping in for anyone else who is struggling on this one.

For me the solution was to restart my device.

Solution 2:

I had this same issue when loading a bunch of very large images (5000px x 5000px) in UIImages. Luckily the images were not supposed to be anywhere near that big and I just needed to resize them.