A wallet that is installed as an app on a smartphone is accessed online and considered to be a “hot wallet” because it is connected to the Internet. This wallet stores your private keys on your smartphone and should not be used to store large amounts of cryptocurrency. Phones are frequently broken, lost, stolen, or breached and two-factor authentication and password-protection is a must when using a mobile wallet. Many consider a mobile wallet to be the least secure of all wallets but highly convenient. Many available apps are designed to be as secure as possible, but extra security measures should be taken when using this type of wallet.
A commonly used mobile wallet is Coinbase, and it is considered to be one of the most secure. As well as being a fiat-cryptocurrency exchange, Coinbase offers one of the most popular web wallets accessible by mobile. Based in San Francisco, Coinbase has 7.4+ million users and is available in 32 countries. What makes Coinbase the most popular choice is that users can easily and instantly buy or convert crypto using fiat currencies such as USD, AUD, EUR, CAD, GBP, CNY and 50+ more. They accept debit cards, wire transfer, or ACH bank transfer for buying BTC, ETH, LTC, and a few other altcoins. Fees and transfer limits vary.
Many experts in the crypto-space consider smartphone wallets to be completely insecure. There have been over 500 million downloads of emoji keyboards: keyloggers, spyware disguised as friendly emoticon keyboards. When you initiate a mobile wallet your bitcoin info or username/password credentials are entered. The malware uses intrusive permissions that allow data to be sent to criminal servers remotely. Additionally, Android devices are riskier than iPhones, and just about any app can spy on them. If you use a mobile wallet, lock it down and do not run third-party keyboards, risky apps, and delete all apps never used. Do not have background apps running, and turn off the hardware ports that are not needed to make crypto-transactions – this includes bluetooth or wifi – and ensure SSL is enabled. Bitcoin transactions over wifi should be avoided.