My second question, Electurm or Blue Wallet, which one you think is better?
For me personally electrum never really worked as expected on android - it was constantly crashing at the most inconvenient places. That said, even if it worked great I think bluewallet is much, much more polished and a better user experience - and it's available on ios as well, which electrum is not.
It's really strange that electrum wallet isn't available on iOS though it is available for MAC OS. Also, they haven't released a better verson for Andriod, don't know the reason for this ?
The popularity they have gained over the time they should have come up with best apps for both Android and iOS.