Wi-Fi slow on iPhone, fast on computer or tablet At our home, we pay for 20 Mbps Internet connection to operator. On computers and tablets we get full speed via Wi-Fi, while on iPhone 7 and iPhone XR we gat max 2.7 Mbps. We live in apartment with maybe 20 different wireless networks.


We tried different channels - no change in behaviour on our iPhones.
We tried phones at our company Wi-Fi networks - we got around 17 Mbps there, so phone hardware is capable of receiving more data.
We bought new modem/router Asus DSL-AC55U which can stream also on 5 Ghz - still same behaviour.
We called with provider on the phone trying to change settings - no effect, still same behaviour.
we have tried on phones change DNS server to manual, we tried googles and others - still same behaviour.


I believe that there is problem with Wi-Fi settings. Anyone has idea how to resolve this issue?
The following observation indicates to a problem specifically for iPhones in contrast to e.g. iPad and maybe related to your problem.

I had problems to convince my iPhone 6s to use the 5GHz band. iPad and iMac did it at once after I switched off the 2.4 GHz in the router. The iPhone would not connect, even after resetting the network settings. The trick I used (not my own idea) was to use two different SSIDs for 5GHz and 2.4Ghz. Even then it took two or three attempts, but now the iPhone connects to the 5GHz.