I suspect that the wifi on my iPhone 6 is malfunctioning, but I'm not sure.
I've been struggling to get decent wifi signal on my iPhone in parts of my house, to the extent that I added a second wifi AP to try and eliminate some deadspots. For the most part, it has worked. However, I'm now wondering whether it was just my iPhone rather than the router. I have a number of reasons:
1. The Chromecast (v1) I use in the kitchen (where I have previously had deadspots for wifi on my iPhone) has no problem connecting to first router (at the other end of the house).
2. My wife's iPhone 6 (exact same model) has no problem connecting to wifi in the same locations where I can't sustain a good wifi signal.
3. Yesterday, I ran a SpeedTest on my iPhone after Spark upgrade our UFB connection from 30mbps to 100mbps, because I was curious to see what speeds I would be getting over wifi on my phone. My PC on a wired connection got 104mbps down/18mbps up (as expected). My iPhone, over wifi of course, got on average about 5mbps down/9mbps up. I ran the test several times, and each time it was connecting to the same server (in Wellington), and was getting good ping times of about 6ms. Once or twice the speed spiked around 30mbps, but curiously I noticed that the throughput would start high (near 30mbps) and then drop steadily through the course of the test (sometimes as low as 0mbps) before rising slightly to give a final result usually below 10mbps. At one point, I lost wifi signal altogether. I ran the same tests on my wife's iPhone (same model), in the same location, immediately after. Not only did her phone not have low speeds (average 30-40mbps download), the throughput was consistent during the test, and didn't drop off like mine did. It also maintained a strong wifi signal throughout.
4. It may not be related, but I have a persistent problem with bluetooth connections on my iPhone. When I connect to my headphones, the signal stutters and breaks off if either my headphones or my phone moves around. I bought a small bluetooth portable speaker, and it often drops a connection from my iPhone. I also had problems with a Garmin VivoSmart last year where the bluetooth connection would drop and reconnect every 10 seconds or so.
To me, this suggests that my iPhone is faulty. Wifi connections (and bluetooth connections) are not stable and reliable, though in each case they can connect. Would you agree that there is a fault with the phone? Or is there some other likely explanation I haven't considered?