Just got the Honor 6+, without a case it reads the ring easily. When I get a case, I'll update and upload a picture to show location.

Moto Razr HD with otterbox defender case. running android 4.4.4 paranoid android rom

the hole in the case is 20mm and is covered once the outer case is back on. I found the ring works from vertical to horizontal in the arc indicated by the green arrow

@MattZ. It depends on which phone and case you have. For instance, I have a moto razr hd with an otter box defender case and to start with it was difficult to find the sweet spot, but once i did, i cut a hole in the hard plastic of the case, which is covered by the outer soft layer, and now it works all the time.

Just got the Honor 6+, without a case it reads the ring easily. When I get a case, I'll update and upload a picture to show location.

@MattZ. It depends on which phone and case you have. For instance, I have a moto razr hd with an otter box defender case and to start with it was difficult to find the sweet spot, but once i did, i cut a hole in the hard plastic of the case, which is covered by the outer soft layer, and now it works all the time.

there are a couple of ways, both can be a bit tricky. the first edit the NFC.apk sound file, the other if your phone is rooted install the Xposed framework app and the NFC lockscreenoff enabler module. If you go to the XDA developers web site and have a look in the forums relating to your phone, you should be able to find some guides on how to do both.
A word of warning though, I tried to edit the NFC.apk file and forgot to back it up, then the changed file wouldn't work so I lost all NFC function and had to do a factory reset to get it back.
I now have a rooted phone and the Xposed app running which I personally think is the better way round to do it. Though rooting your phone also carries a lot of risk.

Moto Razr HD with otterbox defender case. running android 4.4.4 paranoid android rom

the hole in the case is 20mm and is covered once the outer case is back on. I found the ring works from vertical to horizontal in the arc indicated by the green arrow

I'm not sure if this would work with the ring, as it involves running a low voltage through it, but I thought I would mention it as a way of colouring the titanium.
You can anodize your ring with just a couple 9 volt batteries hooked in series, a couple wires, some water with some Tri-Sodium Phosphate (TSP) dissolved in it and a rag or q-tip. Hook one wire to the ring and the other to the q-tip, dip the end of the q-tip into the TSP solution and touch it to your ring. Different voltages bring out different colours.
This idea isn't one I came up with its from Chad Mueller who did a kickstarter for a flat packing camping stove and one of the options is a titanium one and this was a tip if you want to colour your stove. I thought it might be of interest.