Signal is removing support for SMS text messaging on Android

Signal will begin to phase out the SMS and MMS messaging support in its Android app, to improve user experience and to prioritize security and privacy.

Since its inception as TextSecure (an app that used Axolotl’s Ratchet protocol), the Signal for Android application could be set as the default SMS/MMS client.

We have reached a point where SMS support is no longer necessary. We are phasing out SMS support in the Android app to provide a better Signal experience. This was announced today by the company.

Source:
https://www.bleepingcomputer.com/news/technology/signal-will-remove-support-for-sms-text-messages-on-android/