I can echo what he says. The iPhone has absolutely enormous bezels, so much so that the iPhone 6 Plus is definitely larger than my Galaxy Note 3 despite its having a 5.7" screen. That was the first thing I noticed when I held them side by side at a store a few weeks ago.

iPhone 6: 138.1 x 67 x 6.9 mm (5.44 x 2.64 x 0.27 in)

Nexus 5: 137.9 x 69.2 x 8.6 mm (5.43 x 2.72 x 0.34 in)

So 63 cm^3 vs 82 cm^3 in volume, and 92.5 cm^2 vs 95.4 cm^2 in front area.

It's the width that's what you feel when you hold it.

... and width is the only dimension where the iPhone 6 is actually bigger than the Nexus 5.

People tend to hold their phones in "portrait" mode, rather than "landscape". So, width would typically refer to the second largest dimension when talking about (most) phones. Additionally, given that phones are 3d objects, interacted with in physical space, the "feeling" of width would also include the phone's thickness, to some extent.

In this context, the iPhone 6 is actually smaller than the Nexus 5, by about 20%.

Not according to morsch two comments up.

I think you're imagining things because they're almost identical and the nexus 5 is actually slightly narrower.

I've held both and they feel identical. Same vertical and horizontal dimensions and same weight. The thickness isn't even noticeable in your hand.