A free app for Android, by M. Brodski Software.

Crypto Arbitrage shows you the best arbitrage deals and opportunities and how to profit from them. It has a list of crucial pairs of cryptocurrencies (Etherium, Bitcoin, etc.) and flat currencies (Euro, US Dollar, etc.)

How can I use Crypto Arbitrage?

Install the app on your device and make sure it is ready for use. On its interface, when you tap the icon on the right, the buying and selling prices of stock exchanges are inquired for the according to currency pair. The arbitrage transaction is displayed once calculated. 

The app has a calculator for you to calculate the amounts and profits, and charts to display several available charts. To change the crypto exchanges, modify them under settings.