When lightening network will be launch on main net?
it wont…the lightning network is a side chain network and it already works…it is a side chain like application that gets redeemed by a bitcoin or litecoin wallet if and when the user wants to send coins back to mainnet storage…check out "Zap Wallet which is the one that Charlie Lee got Litecoin working on…you can send and receive Bitcoin and Litecoin with other parties as many times as you want and then import the keys into a Litecoin or Bitcoin core wallet…
I have not done more that just look around at it and I downloaded it myself just haven’t played with it yet…can always use testnet coins to play with it though…
here’s the link for zap wallet: zap wallet
Just to let you know that distinct LN clients are already interoperable and that first beta is close.
LN has been tested on Bitcoin mainnet. We may see LN soon (I hope we do). 