A lot of people don't like this place because of the floor to ceiling windows that overlook the junction of old st / kingsland rd and shoreditch high st however what you will realize is that they're perfectly angled to catch the light and provide warmth to whoever is sat inside reading their book at around 2pm.
The people that work there make awesome coffee but they may sometimes be slow and even spill your coffee but they'll always apologize really nicely.
Out the back they have tables with church pews - although if you're there for the wi-fi remember that there's only 4 plugs for your laptop and it gets busy pretty quickly.