How to fix iPhone X + iOS 13 Slow Wifi?

Question

How do I fix slow wifi on an iPhone XR (iOS 13.4.1)?

The boss has an iPhone XR (iOS 13.4.1), and I have an iPhone 6 (iOS 12.4.5). The iPhone 6 gets 100% better Mbps throughput around my house. I have validated my router health and validated network setup on both phones. I have done all the reset/forget network cycling recommended by guides like this and this and this.

I measure the same performance percentage difference--iPhone 6 performs roughly 110% better--in all these tested scenarios:

• 802.11 b/g/n 2.4 GHz network connection on both phones, simultaneously
• 802.11 ac 5 GHz network connection on both phones, simultaneously (first screenshot)
• Bluetooth off (second screenshot)

My test was:

1. hold both phones in hand
2. test average Mbps download speeds using Wi-Fi Sweetspots app
3. average over ~10 seconds
4. test 6 different spots around the house
5. record results

Here are the side-by-side results of the latter two tests; left side is iPhone XR + iOS 13.4.1, right side is iPhone 6 + iOS 12.4.5

Test with bluetooth radio off on both phones:

In both tests, "Spot 4" is standing directly next to the Wifi router.

Update:

Here are the recorded results in a Google Spreadsheet for at least 6 tests. The 5 of the top 6 results were for the iPhone 6 + iOS 12.4.5 combination.

Update 2:

• both devices were tested without cases.
• I have tested on four different routers: 2 models of Netgear, TPLink AV600, cheap-o ActionTek. Results were consistent across all 4 routers: iPhone 6 consistently had 100%+ better throughput.

Update 3:

My wifi was assigned to channels [email protected] and 44@5GHz, which my network analysis showed to be the only thing in the area on that channel. Also conducted a second test on alternate channels, with exclusive access; same results.

Update 4:

Both Phones were restarted occasionally, but not between every documented run. There was definitely a restart in the iPhoneX at least twice: once when the documented tests started, and once when I upgraded it from 13.3 to 13.4.1. Over the course of the few weeks that I have been observing the throughput metrics, the phones have been restarted ad-hoc and the slow relative behavior persists.

Update 5:

The following settings were in place at the time of the test:

• Automatic Updates: Off
• AirDrop: Receiving Off
• Handoff: Off
• Wi-Fi Calling: Off
• iTunes Wi-Fi Sync: Off

Answer 1

There is nothing to fix

What you measure are hardware and software differences.

The 2 iPhones you compare have a different internal density of components and different radio hardware. With higher density of components a lot of internal reflections occurs very near from the emitting source of radio frequency. Then the interferences caused by these reflections have a heavy impact on the signal / noise ratio of the radio signal.

To give you an image of what happens with short distance reflections just stick a large plane of plastic in front of a speaker and compare the sound quality with the speaker you left free.

Recommandations to make correct measures

If you would like to improve your comparison of hardware and software performance in the WI-Fi field, I would suggest to remove any internal source of load:

• Stop all automatic update:

  Settings > General > Software Update > Automatic Updates: Off

• Stop AirDrop:

  Settings > General > AirDrop: Receiving Off

• Stop Handoff:

  Settings > General > Handoff: Off

• Stop Wi-Fi calling:

  Settings > Phone > Wi-Fi Calling: Off

• Stop iTunes Wi-Fi Sync:

  On your Mac, iTunes disable the automatic syncing of your iPhones and the backup on Wi-Fi.

Answer 2

There could be multiple reasons why your WiFi is slow. Did you put the router behind something because some objects that are really hard or impossible for Wi-Fi signals to pierce through. Another thing you can try is changing your WiFi channel. To do that you can use Nirsoft’s WifiInfoView(https://www.nirsoft.net/utils/wifi_information_view.html)

Answer 3

As discussed in the comments, you did a sufficiently detailed comparison of both devices speeds, and covered the things you can try with software. Therefore I suggest to test the hardware:

Test another iPhone XR.

If the results are the same, the wifi unit in the iPhone XR is in some ways worse than the one in iPhone 6. If the results of the second XR are much better, the first XR is a defective unit and should be replaced by Apple warranty.