In Oslo, Norway, one of the major taxi companies has an app called Taxifix. You reserve a maximum price in advance. If it ends up cheaper, you only pay the actual price. If it ends up more expensive, the taxi company covers it. You can also see where your taxi is on a map while you are waiting

I think other companies have similar apps, but I always use this company as they usually have more competent drivers and reasonable prices

That also works in göteborg.