Konnichiwa Sreekanth san,
Whatever you have heard about the Japan’s railway network is true. There are a few other mobile applications that I can suggest you apart from Google Maps like, HyperDia (Av...ailable in English, free but includes in app purchases), Japan Travel by NAVITIME(Multilingual, free but includes in app purchases), Japan Transit Planner by Jorudan(Multilingual, free) , Yahoo Trains 乗換案内 (Japanese Only) but after consulting with my team members and my own personal experience, I will recommend you to use Google Maps as it is very detailed and easy to use especially for a newcomer in Japan. Google Maps is also surprisingly good when it comes to providing train navigation instructions with accurate timing. Not only foreigners but I have also noticed locals use it so it must be reliable.
Other benefits of using Google Maps over other mentioned applications:
1. It is multilingual.
2. You can save map for a region and the train route offline whenever you plan a trip.
3. Detailed information like coach number near to the escalators, elevators and stairs, peak hours, information about transfers, ticket gates, etc.
4. Because stations in Japan have multiple exits so whenever you are using Google Maps for navigation, information like nearby exit to the destination and features like ETA, street view are also available.
Anyhow, this is just a personal preference you can also try using different navigation applications which are only in Japanese and are widely used by locals like Yahoo Trains 乗換案内, NAVITIME, etc. once you are here.
I hope this was helpful!
Regards,
Tushar
