Unlike many other big cities around the world, Shanghai does not have many taxis and it can be quite difficult to hail one. Car hailing or car sharing apps like Didi are very popular in Shanghai for that reason. If you walk out of your apartment in the morning and just try to catch a taxi to go to work, you might very well find yourself in quite some trouble unless you are near a hotel where you can get one.
Taxis are usually some old Volkswagen cars and the meter starts around 14rmb. Depending on the distance and time of the day, Taxis will not be cheaper than Didi cars but are also not as comfortable.
Taxis can also be called from the Didi app among many others.
Another app that is specifically for taxis is Dida Chuxing (嘀嗒出行) but unfortunately is available only in Chinese. You can see their website here:
Otherwise, read our article about Didi here.