For some reason, whenever I plug my iPhone into my work laptop (Lambda Tensorbook), the phone charges very slowly. The laptop only has USB 3.1 ports, so it should be charging the device with around 900 mA of current. I tested the actual output of this USB port, and it was only at 500 mA of current, which is usually what USB 2.0 ports can provide. I have tested the ports with other devices and have seen it provide up to 900 mA of current for other devices, but I'm not sure why it won't provide this level of current for my phone. I've never had any problems using the USB 3.0 ports on my MacBook, as I always get faster charging speeds on that compared to my work computer. Has anyone else had issues with slow charging speeds with non-apple computers? Is there any way to improve the charging speeds?
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All the way up to iOS 9, Apple used to let 3rd party apps show the charging and discharging current. In iOS 10 they shut the door on that (oddly). Probably because they had begun secretive throttling.
Since I've still got a phone running IOS 9, I can see the charging current. And what it shows is an eye opener.
If the charge cable isn't inserted just right into the Lightning port, the phone will charge but at a very reduced current. You wouldn't be able to tell just by looking at the phone's charge indicator, as it still shows green - but it's charging really slowly.
Then if I reinsert the cable & try again, I can get the full charge current. But sometimes it takes a couple tries. My charge port is showing its age.
So although you've got a"fast charger" it's likely not putting out much juice. Unfortunately there's no way to see it first hand with the current versions of iOS.
Try using a genuine Apple wall charger. Either the little 5 watt cube that came with the phone or a 12 watt iPad charger. The iPad charger is fast & I've never had a problem with it.
Since I've still got a phone running IOS 9, I can see the charging current. And what it shows is an eye opener.
If the charge cable isn't inserted just right into the Lightning port, the phone will charge but at a very reduced current. You wouldn't be able to tell just by looking at the phone's charge indicator, as it still shows green - but it's charging really slowly.
Then if I reinsert the cable & try again, I can get the full charge current. But sometimes it takes a couple tries. My charge port is showing its age.
So although you've got a"fast charger" it's likely not putting out much juice. Unfortunately there's no way to see it first hand with the current versions of iOS.
Try using a genuine Apple wall charger. Either the little 5 watt cube that came with the phone or a 12 watt iPad charger. The iPad charger is fast & I've never had a problem with it.
Ah, I was under the impression that the iPhone XS fully supported USB 3.0, but it seems like there is only partial support when connected to specific computers. As stated on this website (near the bottom), https://support.apple.com/en-us/HT204377, Apple displays and Macs are able to give extra current to certain Apple devices (such as iPhones and iPads), which allows them to charge faster than USB 2.0, USB 3.0, or even the standard 5W wall charger (as shown on that website, charging from a MacBook USB port provides 1100 mA of current or 5.5W of power)
Not sure if you are running windows but if you are by chance running windows you can install an app call asus aicharger and it will increase the charging speed of your USB ports if it detects an iPhone or iPad.