From Tripadvisor.com reviews of Costa coffee Prague:

“We had breakfast here everyday during our stay“: I love Costa Cafe! We stayed at an Airbnb apartment 5 minutes walk from this Costa Cafe so we had the pleasure to have breakfast here EVERYDAY. They have delicious cake and croissant to go with your favorite coffee. Try their clementine cake, it is to die for! The coffee shop is located inside the tesco store.

“When you need a place for coffee and internet in Prague“: Unlike Costa Coffee in UK they seem to be positioned more upmarket as an internet café with power points for your computer (you never find that in UK); so there tends to be fewer people waiting and places to sit and work in peace. The nice barista girl speaks good English and I think the other staff also do – but this is normal for young people in Czechia.

View this post on Instagram

Taky musíte mít ke kávě vždy něco sladkého ? 😋❤️ #costacoffee #flatwhite #icecoffee #latteart #carrotcake

A post shared by Costa Coffee Česká republika (@costacoffeecz) on Jun 24, 2019 at 1:18am PDT

“Great staff, great place, great atmosphere!“: We lived at CC during our time in Prague. Every morning before the gym-CC! Before heading out for the day of checking out sights-CC! After dinner relaxing and reflecting on our day-CC!
This place had particularly good staff. They were so friendly and spoke pretty good English. There was one employee that was very quiet and refused to speak English, but no workplace is perfect. You accept the good with the bad!
The coffee for us was always good, never a complaint. We rarely had sweets or snacks, but the few times we did, they were good too. The atmosphere was always welcoming. People working on laptops, haveing tea and chatting, or just dropping in to grab some java! All in all one of the best coffee places we visited in Prague.

“Great coffee“: Best coffee I had in Prague! Latte just as it could be! Service is really friendly and fast will be back 😉 and they selling traditional Czech sweet! Perfect touch!