This app was mentioned in 3 comments, with an average of 1.33 upvotes
It's not free, but it's the best one I've found. Far better than Juice and everything else mentioned.
+1 for Blowtorch
There's also ANSI Terminal Mobile, but it's not free and it's got a bit of a lag to it... but it's the best app I've found as far as ANSI Art support goes.
I have not tried this app, but it looks promising: ANSI Terminal Mobile by Hordequester ($1.00): https://play.google.com/store/apps/details?id=com.hordeq.ansiterminalmobile
However, on a tablet (held portrait instead of landscape), my.ftelnet.ca is really a great solution. Even on my S5 phone it works pretty well.