The apartment is very well positioned for local transport (trams, subway) and is just a short walk to the main square in the old town, Charles Bridge and everything the old town has to offer. There's a super market right next door, a very nice jazz club and some nice cafes such as cafe louvre and cafe slavier, and a fabulous ice cream shop Crème de la Crème Across the road that my daughter made full use of (several times per day).
Ramona provided recommendations for a number of restaurants and they were all great. I recommend pivovar narodni for typical Czech food (don't underestimate the size of the portions, and the unfiltered beer is very nice).
Check in was easy, and arranging transport via the host made pick up from the airport hassle free and was reasonably priced. We'd definelty recommend this apartment. We wouldn't hesitate to book this again next time we return to Prague.