This application was downloaded and set up by over 10M users and its most recent stable update was on Oct 16, 2020. Samsung and Sony users download the app quite often. A free .apk file of Plus Messenger 22.214.171.124 can be downloaded from Droid Informer and you can have a look at users' reviews on this site. Prepare 17 MB of free space on your device for this app setup package and keep in mind that it runs on Android 4.1 and above.
As users mention, you can find the best interface and useful features among the pluses of the app. As users see it, there are several drawbacks, they are network errors and a battery drain.