A much more portable console with smaller screen and maybe 1080p resolution and running at the docked performance level while portable. More flash memory and much lower price. They simply move the Switch into a true portable position similar to 3DS and DS. Docked may become less important and we may not even see weak versions of ps4 and xbone games it will simply rely on games written exclusively for the Switch like 3DS. Nintendo will have to react to what is available though. Android devices are getting more powerful all the time and are already not that far from Switch. I saw that the iphone 8 plus in one benchmark (GFX open cl) scored something like 6,700 compared to about 3,300 for the Shield box which runs the Tegra X1 at full speed, slightly faster for GPU and almost double for CPU compared to Switch (although 1GB less memory) and mobile chipsets rapidly improve so will the Switch be viable when people's phones and tablets are much more powerful for far less money with a wide range of much cheaper albeit inferior playability generally games. Consumers really will dictate how long the Switch is viable. In 3 years time the Switch may have difficulty selling. I'm not saying it will but its possible. Nintendo will monitor sales and analyse them to work out when they need to release a new console. If Nintendo are forced into heavy discounting to shift consoles I suspect they will be more than keen to bring out something new.
