What is the World Transit Maps - Railway & subway networks application, how does it work?

According to the introduction of TOKYO STUDIO INC., World Transit Maps - Railway & subway networks is a Maps & Navigation app on the Android platform. There is currently a 7.1.0 version released on Mar 01, 2020, you can see the details below.

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Countries / Regions
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The coverage area will continue to expand steadily in the future.

[Asia]
- Hong Kong
MTR, Airport Express, Hong Kong Tram, Peak Tram, Light Rail
- Japan
Shinkansen, JR, railways, subways in Tokyo / Yokohama / Nagoya / Kyoto / Osaka / Fukuoka etc.
- Malaysia
KTM, KLIA Express, KL Monorail, Kuala Lumpur LRT
- Singapore
MRT, LRT, Sentosa Express, cable car
- South Korea
KTX, KORAIL, Airport Express (A'REX), subways & metro in Seoul, Incheon, Daejeon, Daegu & Busan
- Taiwan
High-Speed Railway (HSR), Taiwan Railway (TRA), Alishan Forest Railway, Taipei & Kaohsiung Metro
- Thailand
State Railways (SRT), Airport Rail Link, BTS (Skytrain) & MRT in Bangkok

[Europe]
- France
  Eurostar, Thalys, TGV, Ouigo, Intercités, TER, Transilien, RER
  Métro in Paris, Lille, Lyon, Marseille, Toulouse & Rennes
  Tramway in Strasbourg, Mulhouse, Grenoble, Montpellier, Bordeaux, Nantes, Caen etc.
- United Kingdom (England, Wales, Scotland & Northern Ireland)
Eurostar, South Eastern High Speed, National Rail
Underground (Tube), metro, tram in London, Manchester, Newcastle etc.

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Major Functions
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- Railway maps for multiple languages
(Offline browsing is available if already downloaded)
- Transit route search
- Trains operation status
- Street maps
- Hotel reservation
- Timetable of stations (Japan Only)
- Photo gallery of stations

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Upgrade
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You can now use the railway maps and the transit route search of all provided countries / regions with regardless of the free / paid plan.

“Rail Map Basic” (Free)
- You need to watch a video ad when switching between countries / regions.
- The railway maps or other screens show ads.

“Rail Map Passport” (One-time-purchase)
- Fast Lane: Video ads are not displayed when switching between countries / regions.
- The railway maps or other screens show ads.

“Rail Map Premium” (Monthly Subscription)
- Fast Lane: Video ads are not displayed when switching between countries / regions.
- Ads are disappeared on the railway maps or other screen *1.

*1 Some ads may be shown on the screen such as the result of transit route search or others.