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Get No Last Seen～shinobi old version APK for Android
Shinobi lets you read messages without marking them as "read" or "last seen"
"Shinobi" is an Android app that enables you to read messages without marking them as "read" or "last seen".
Usage is very easy.
When a message comes, Only open the "Shinobi" in the Notifications
Devices using Android 5.0 and later have new settings.
http://awalker.jp/app_chirami/en/settings2.php