I have found the reason why the FFMPEG used 100% of CPU and why jerky video displayed on devices. It is because I did not mentioned the frame rate.
-r 24
ffmpeg -i "rtmp://localhost/oflaDemo/33/hlsopt6 live=1" -y -c:v libx264 \
-b:v 1000k -r 24 -vprofile baseline -preset medium -x264opts level=41 \
-threads 4 -s 480x360 -map 0:v -c:a libfaac -b:a 160000 -ac 1 -hls_time 3 \
-hls_list_size 2 -hls_wrap 10 -start_number 1 hlsopt6.m3u8
Now it is playback smoothly on all devices and also FFMPEG take less CPU.