I use Electrum with just a passphrase. I don't actually have a digital file that once can steal, I simply have a written sequence of words that I keep in a safe place. I've actually memorised them but I'm too paranoid to destroy the paper copy. I write them in to reconstruct the private key only when I need it. I do this on an old laptop that is only used for this purpose.<p>For my personal convenience vs security threshold it's quite helpful but for those who trade daily it's probably too much effort.
Others have covered your desktop options well.<p>On mobile, any of these are fine:<p>* Green Wallet<p>* Coinomi<p>* Coinbase Wallet (Wallet app. Don't keep your Bitcoin in an Exchange. It is not under your control at that point.). If you have privacy concerns WRT governments, don't use this option.<p>For more security:<p>* Use hardware wallets, such as Trezor<p>* Paper wallets in a bank's safe deposit box.
For strictly Bitcoin a colleague showed me OpenDime[0] which is pretty cool. To get the secret key the device is physically altered.<p>Otherwise I have a few hardware wallets around but haven’t used them much as I didn’t like that some required a Chrome app or other less than ideal, from my perspective, setups.<p>[0] <a href="https://opendime.com/" rel="nofollow">https://opendime.com/</a>
Personally, I use Jaxx Liberty on my iPhone.<p>I have the backup phrase in a safe.<p>I do not have a lot of value invested in crypto assets. If you intend to store larger amounts, I wouldn’t recommend this set-up.