I recently came back home after spending 20 days on a business trip that touched Bangkok, Beijing, Seoul and Tokyo.
The limited time available and the need to carry over my business objectives severely limited my ability to fully appreciate the different cities.
I only had some time during the week ends (when I was not using them to move from one country to the other) and after the office time.
Walking around in Bangkok and Beijing was very easy.
Thanks to the availability of the city maps for my Nokia phone I never had issues to find specific places and the public transportation (boat, skytrain and tuctuc in Bangkok, subway in Beijing) was very affordable and not difficult at all to use for a foreign person.
Moving around in Seoul and Tokyo was more problematic, mainly because of the lack of offline maps on the phone (I had both a Symbian Belle and WindowsPhone8 devices).
I hoped to use an online service, but it turned out that the prepaid sim card available in Korea work only for local people or foreigners with a permanent or long stay visa.
Having no offline nor online map led to a limit in the freedom of walking around in Seoul and this got worse in Tokyo as the rain season had just started when I arrived thus making random searches for places very inconvenient.
Language was a barrier in many cases because only a small percentage of the people was able to communicate in english: this is not uncommon in Italy either; it is not a specific issue of the far east.
Yet communication somehow happened: pointing at items and using google translator (when there was some wi-fi coverage) helped a lot.
Even with all the limits of not being a full-time turist it was a very interesting and exciting experience and I would be happy to be able to get in that area again in the future.