I dont have a computer right now.
Just an android and an iPad... So desktop wallets are not an option for me.
That said, which between a mobile or online wallet do you experienced investors out there prefer and why?
Not really any difference. Your wallet is only as secure as your device. I'd say if you're going to not download a desktop client then use blockchain.info and enable 2fa(install google authenticator or whatever on your other device). Otherwise, use mycelium. Both are pretty established in terms of security.
It's really up to personal preference, as long as you hold your own keys you should be fine.
There is actually a huge difference. But the difference is not depending on if the wallet is "online" or not. It depends if the wallet gives you access to the private keys, which most wallet apps have, whereas most online web wallets don't have.
To OP:
on android, go use Copay or Mycelium.
on iOS, go with BreadWallet.