Not much, XRP, XMR, ETH, LTC, maybe some others later on.
All of these are supported by the ledger nano s.
If the overall $-amount you hold can
absorb the purchase of a hardware wallet, go for it.
It is the best combination of security and convinience. You'll be able to access them all the time with ease, while the private keys stay in a secured offline environment.
For holding the most common coins (see:
ledgers supported assets) a hardware wallet probably would be the
best option.
I have Coinomi on my phone but I'm not comfortable on storing real money on software built for cellphones.
I can understand that doubt.
But running an android emulator on a linux machine to store your coins SHOULD be safer than desktop wallets on windows. But no guarantee on that.