You could try (if you haven't already) setting your Wowza app's StreamType to
live-lowlatency. Note that there will always be some latency in your workflow, via ffmpeg doing the encoding, Wowza doing the re-streaming, your Android app replaying the stream, so 3 seconds may be a pretty reasonable delay. How much delay is involved if you test using the Wowza Test Player in the Engine Manager or playing back using something like VLC? Or alternatively if you create a stream file in Wowza with the source RTSP stream as its content. If the delay is less in those tests then there may be not much more that can be done prior to it reaching the Android device.