the best web wallet for now only blockchain we can access it from website and mobile app so easy to access and we can set the fees low or high and the security feature is good enough like email and sms verification 
and for friendly reminder that never leave your funds at any exchanges it's not a safe place
After a full review of the blockchain and a detailed analysis of the features it pretty says that blockchain should be the best Bitcoin web wallets. Blockchain.info most popular Bitcoin wallet today. I have no argued Hardware wallets and secure offline wallets are good options though. and for friendly reminder that never leave your funds at any exchanges it's not a safe place