Try Xapo, As they are really convenient when sending bitcoins because you don't have to pay the miners fee as they already eliminated it .
But just like what the others said, Only keep a small amount of money in online wallets as they are very risky because most of them don't give private keys .
And don't try coinbase as they are very strict, every transaction is regulated they can block or even terminate your account .
Xapo is okay but I like the other wallets way more if I have to be honest, its of course also how you look at it but the fact is that the blockchain is also good and pretty good secured for a online one.