[khedoros1]

Something like that. They actually look like they might have coiled springs providing tension to the leaves on the phone side, and then contacts kind of laminated on ribbon cables in the back panel.

- contacts visible in back cover (the 4 yellow contacts for wireless charging are the easiest to see): https://i.ytimg.com/vi/-RWgjtEwQYQ/maxresdefault.jpg

- spring-loaded contacts in the phone (3 around the camera, 2 on the opposite top corner, 4 match up with the wireless charging points): http://images.anandtech.com/doci/7517/Nexus5-1552.jpg

In mine, the back cover flexes, and contact isn't always maintained for all the connections. I've cleaned them with contact cleaner, and alcohol, tried bending the leaves to provide more pressure, etc. I also replaced the back at one point. Like the original, it would be fine for a while, then need readjustment. The body of the phone has a few thin, brittle parts, which started cracking (the back really wasn't designed to be removed often). I feel like the wear+tear on the phone body and constant mechanical maintenance just wasn't worth it.

Prior to opening the sucker because of the wireless charging not working, there shouldn't've been any finger oils on the contacts (or, I'd hope).