Mobile apps required. Alert app and Feedback app

I need an app where a community of persons can be alerted to notices as the need arises and an app to get community feedback on events, issues etc

Here are two examples of what I mean

https://play.google.com/store/apps/details?id=com.intrinsicdata.bimalert3

https://play.google.com/store/apps/details?id=com.intrinsicdata.bosslistens