スマート留守電 is a text-to-speech service that allows you to convert voicemail messages into text and automatically forward them to your LINE or email. With over 200,000 users, this app offers a convenient way to manage your voicemails and stay connected even when you can't answer your phone.

One of the key features of スマート留守電 is its ability to automatically forward voicemail messages to up to 10 different destinations, including LINE, email, Slack, and smartwatches. You can also consolidate voicemails from multiple devices into one app, making it easier to keep track of your messages. The app supports over 14 languages, including Japanese, English, Chinese, Spanish, and more.

In addition to its convenience, スマート留守電 is also recommended for security purposes. By setting up voicemail forwarding to your family and relatives' LINE or email accounts, you can ensure that important messages are never missed. It is also useful for teleworking, allowing you to receive voicemails on your work phone or mobile device and read them as text, even when you can't take calls.

Please note that you need to have a phone line with call forwarding functionality from one of the supported Japanese telecom operators to use this service. The app is available for free with a monthly subscription plan of 319 yen.