We have tested as low as 2Gb and have had success. But your phone has 3Gb with the game running at almost a 1 GB that leaves just 2GB for every other app/OS RAM need. I think comfortably you would do better with 4Gb or even 6Gb. New flagship phones are sitting at 12Gb.
We are going to be releasing smaller games for Android. These are coming in currently at less that 100mb. So that should really help offset these problems.