I think one of the biggest breakthroughs in wireless connectivity was, when looking at it from a smartphone point of view, when Android pioneered tethering, i.e. the possibility to share a cellular connection with other devices over Wifi. However, one thing that didn’t happen over the years was that a smartphone can be connected to a Wifi hotspot as a client, e.g. at a hotel, and then share this connection over Wifi with other devices instead of the cellular connection. By accident I found out that one of my devices is now actually able to do just that!
Not that this is a terribly important function for me but there are scenarios where this could be quite useful. When I’m at a hotel with a multitude of devices, for example, with cellular connectivity being bad. In such a scenario one would only have to get past the paywall or landing page of the hotel with one device instead of repeating the tedious exercise with each device. The smartphone I discovered that supports this is a Samsung Galaxy S9. At first I couldn’t quite believe it but there are other reports out there confirming my observation. Very well done, Samsung!
that was working at least from Sansung Galaxy 7 series onwards, maybe even 5 series (but I don’t remember exactly)