Hello Laxmi,
As a general rule 3 chunks are required by iOS devices for streaming to begin. Each chunk is set to 10 seconds by default. So that would be around 30 seconds latency.
If you use a keyframe interval of 1 frame per second you can lower the cupertinoChunkDurationTarget to 1 second(1000) and get the latency down to closer to 3 seconds.
Also, you might experiment with a setting of “1” for cupertinoPlaylistChunkCount but probably not a good idea for iOS.
This guide explains the configuration in more detail:
How to configure Apple HTTP Live Streaming packetization (cupertinostreaming)
Thank you, and I hope this is helpful for you. Please let us know if there is anything else we can assist you with in the future.
Salvadore