Hi,I am using Signal on replicant. Just download the apk file from the signal homepage and open it. Then it will be installed. But keep in mind to upgrade to the new replicant version fist 6.1 003, otherwise yout system will crash.
I described the problem here: https://redmine.replicant.us/boards/9/topics/14639?r=14668#message-14668
In general it works fine with replicant.
