For IOS, there's Cryptonator (best one so far in terms of interface and usability), Coinbits (You can find all the Altcoin as well however not user friendly as far as finding the different alts are concerned also you need to pay to remove ads) and BraveNewCoin (it's like the coinmarketcap.com for IOS) to mention a few... A really good one that's for Andriod is Bitcoin Checker where you could find just about all the Alt coins and you could setup customs alerts by percentage. Hope this helps and looking forward to seeing more bitcoin/altcoin tracking apps..