The NHK World app is a free app that pushes notification on disaster and emergency information in English, which will be useful for non-Japanese readers. This includes alerts on earthquake, tsunami, and volcano warnings issued by the Japan Meteorological Agency. The app will also send messages from J-Alert, a nationwide warning system in Japan that broadcast alerts to residents through cellphone, in English to app users.
The NHK World app is available for free on Google Play and Apple App Store.
For more information on the app, please refer to https://www3.nhk.or.jp/nhkworld/upld/thumbnails/en/information/info_20180125_en.pdf