Had a wonderful stay at Charlotte's place in Shoreditch! The flat is really cute, close to transportation, and only a short walk away from some great restaurants and the Spitalfields area.
Some helpful tips for future guests:
Getting a SIM card is much cheaper than renting a mobile wifi. "Three" is a good one — you can pick one up almost anywhere (like the Sainsbury's near the Airbnb). Be sure to "top up" right away at the store, then go online and choose which plan you want to allocate your allowance to.
Being from NYC, we were surprised that not much was open after ~18:00! Even convenience stores close; very few places are open 24 hours. So if you need to get something like toothpaste or shampoo, definitely do it early in the day, even if that means you'll need to carry it around with you!
Walk down to Spitalfields to a restaurant called Blixen: the food is excellent, and the cute indoor garden is open Tuesday - Saturday (iirc). But don't over-order; they don't do takeout.