for the smaller crypto's I use the local wallets provided by their companies, for the larger cryptos I use exodus running on a OS that boots off USB drive. works very well as I can even boot a virtual machine on my main PC using the USB drive. plus I cloned it so one stays in the safe. On Exodus you can keep bitcoin, ethereum, and about 4 other decent cryptos. and the wallet works great too, has a built in exchange linked to shapeshift