Electrum is the best wallet in my opinion. However, I think that will be awesome to create a Multisig wallet Desktop.
Noob here: Say I buy a currency with Cryptopia, the secure thing to do is to move the coin to a wallet and not keep it at Cryptopia? I have a Mac and iPhone what wallet should I use and how would I transfer from Cryptopia to that wallet?
Mobile wallets on Android are the easiest to use and very well maintained. I would recommend Mycelium. On a desktop system, Electrum is very good. But, best option is to use a hard wallet. It means your bitcoins or other tokens are physically stored there, for example, I advise you to use Ledger Nano S.