Hmm. IMO the best multicoin wallet for me at the moment is myetherwallet.com. It's ETH wallet and ERC20 token wallet. It's very secure and easy to use but you can't store your BTC in here. But there are some fake website MEW website so you should be careful when you want to log in your MEW wallet, take a look at the website address before you fill your private key in.
That's not the best and that's not a multicoin wallet, that's really an Ethereum wallet. Jaxx and Coinomi are good because they are easy to use, but there are security vulnerabilities in both. Google them.
Plus in the case of Coinomi. They didn't handle the situation professionally when a user told them about the vulnerability. There was a funny blog about it. You can google that too.
Exodus is the winner for now which has no security issues reported.