Starting 2016, tourists visiting Japan will have access to free Wi-Fi service, thanks to an initiative led by the Japanese government, NTT and KDDI. Until recently, visitors in Japan have had difficulty accessing Wi-Fi networks (except the ones in Starbucks) because login screens don’t have English language instructions. The Japanese government wants to improve access to communications around Japan for tourists in preparation for the 2020 Tokyo Olympics. Tourists can obtain IDs at airports when they show their passports and they can use these IDs to get free Wi-Fi in train stations, airports and other locations frequented by foreign visitors.
Two years ago, I posted an article on free Wi-Fi in Tokyo and Fukuoka. Since then, I noticed that the number of free Wi-Fi hotspots in Tokyo has increased dramatically, especially in cafes. If you are spending several days or more in Japan, my advice is to rent an iPhone from Softbank at the airport. The rates (voice and data) are reasonable.