Which wallet do you consider for ERC-20 tokens and how safe is it?
MyEtherWallet is the best wallet to store ERC-20 tokens. MEW is secure until you give your private keys to hackers. You should not open unknown websites or harmful links. You can use MEW with a hardware wallet (Nano Ledger, Trezor, keepkey etc). You can use MEW with metamask (a chrome extension). Mew is very easy to use and you can create a new account in seconds.
For those who love to send/receive cryptocurrencies via smartphones
Trust wallet will do the work. Trust wallet is the official wallet from Binance (The number one exchange).