Allo hadn't been updated since January of last year, then in December, Google announced Allo's planned obsoletion. Allo will be shutting down today and the messaging app's landing page now shows a Goodbye message that recommends users switch to Android Messages. This is interesting since RCS on the Messages app still isn't widely available but slowly getting there. Google Allo launched in September of 2016 and the messaging app (which was confusing to see launch alongside Google Hangouts and Android's SMS app "Messenger"), and along with it, debuted Google Assistant. At first, you'd only...
Source: https://www.gsmarena.com/google_allo_officially_shuts_down_today-news-35897.php