Seoul

Spend a few hours and learn the Korean alphabet (not that hard) and Google some names of Korean dishes + it's spelling in Korean. It will help a lot as most restaurants only have Korean menu's and often without pictures.

As mentioned previously on the reviews, it's a little hard to eat alone, but Gimbab Chonguk (김밥천국) is everywhere and 24/7 - no one will bat an eye. Also look for places that "specialises" in dumplings, They are usually "alone-eating" friendly. And so are ramen places as well as Korean "chinese" restaurants - Jajangmyeon (자장면) is very good and super addictive. Bibimbab restaurant places are fine too. Actually, it's not that hard to eat alone in Korea. The "group" meals are generally quite obvious and will be things like BBQ. You'll figure it out.
Do Get used to kimchi and spicy food otherwise you'll end up eating the same thing all the time. Be adventurous. Challenge yourself and eat an octopus alive (산낙지). If you're really brave try 보신탕 before authorities close them all - I haven't but a lot of Weagukins (foreigners) secret do.

Cafe's generally have really good wifi, as you would expect from one of the most connected countries in the world. Expect to pay $4-6 for a latte and maybe even more at Starbucks.
Best cafe's are usually around Hipster areas and Universities. Indie owned cafe's are awesome.

Nightlife is great, probably amongst the best in Asia. Can get very expensive especially at night clubs in Gangnam where it would could be like $10 for a beer - in that case you can still get drunk for $2 with soju just outside at 7Eleven.

Winters are stupidly cold and summers can be brutally hot & humid. Go between April and June or September to October. They have cherry blossoms in spring which is beautiful and so are the autumn leaves.

Lived here for many years. It's a cool place and vastly underrated.

Seoul is continuously becoming more expensive and cost of living will soon be comparable with places like Tokyo.

Seoul is lovely but still has some challenges for nomads. Korean food is great, but most restaurants are used to serving groups, or at least couples. Many times you'll simply be refused service entering a restaurant alone. Unlike Japan, eating alone is stil frowned upon in Korea and mostly impossible. Exceptions are of course expat areas like Itaewon which are more used to it. Also outside signage and menus are mostly still in Korean, without any English translations generally. Even if you learn the Korean characters, you won't know the words, so this makes it impossible to order. This is slowly changing though, especially in hipster areas. You might ask "why does this reviewer care stuff is in English or not, they're in Korea, what does he expect?". Well, it's 2018 and Korea presents itself as an international country, English should be the default sub text. There's more challenges, it's very difficult to meet Koreans, you'll always be seen as the "token" foreigner in social groups. This is understandable and to be fair it's much worse in Japan than Korea. Unless you're in expat areas, you'll feel fairly isolated because Koreans will generally avoid you for fear of having to speak English. This makes it a potentially very lonely experience for any nomads. This is kinda vicious because Koreans look down on people that are alone. Hence the group-eating thing. Solutions to that? Come here with a group of friends. You'll have a MUCH easier time.

Koreans have the image that 'foreigners' like ie, Europeans, can't handle spicy food. Don't be a wuss. You're making us look bad.

The best area in Seoul now is called Seongsu, it's like the Shoreditch/Williamsburg of Seoul. Lots of old warehouses used as cafes etc. Fashion desginers. Boutique art exhibitions. Go live around there, it's great!

You can get unlimited 4G data sim cards from KT at a handful of places. Incheon airport has them, and the KT office near Hongik Univ. station (behind big Samsung building). There's a storefront on the ground floor (street-level), but they will tell you to go inside the building and to the fourth floor. It's kinda tricky to find, so just go to the store and they will explain. I think I paid about 30k KRW for 1 week of unlimited data.