| Do not leave coins on an exchange. Any digital currency is only yours if you control the private keys. All recommendations are for Bitcoin. Most secure: A hardware wallet like the "Trezor" or "Ledger". Good balance of security and usability. Gives you a backup phrase in case the device is lost. Backup phrase fits on a piece of paper, can be made as secure as required. Keep backup phrase in multiple locations. Cheap and secure: (encrypted) paper wallets generated from https://www.bitaddress.org , with backups stored in multiple locations. Bad usability, but can be made as secure as you want/require. Easy, reasonably secure, not for large amounts: "breadwallet" for iOS/Android. OSS, user friendly, but not recommended for long-term storage. As most modern wallets do, this one also gives you a backup phrase to be stored on paper. As for exchanges, I'm in Europe and trust bitcoin.de.
On Reddit there have generally been no major complaints about Bitstamp, a few about Coinbase, and a lot about Kraken. |
Ledger Nano S - https://amzn.com/dp/B01J66NF46/ $146.50 | referral: http://amzn.to/2eYkJSQ
You may find better prices (back ordered) on their respective sites linked elsewhere on this thread.