You will love Jan and Sarah's apartment, but even more so you will love the hosts. Jan and Sarah are some of the most accomodating and pleasant airbnb hosts you will ever meet. The apartment is in the middle of Prague, an easy walk to everything, but at the same time quiet and secluded because it is in the interior of a building with very thick walls and no sound exposure to the surrounding active area of Old Town Square. There is lots of space to spread out with a well supplied kitchen. Security is excellent. You may be able to arrange a pickup and drop off at the airport with Jan and I would highly recommend if that is available. This place is that happy combination of great hosts and and a great apartment.
For a great tour of Prague walk out to the area in front of Cartier for a Sandeman tour of town or the castle. Cross the Charles Bridge and go down the stairs to the left by the river bank to Gothika restaurant or the one adjacent for a great view while dining. Take in a concert at the Rudofinum.