I stumbled across the Gekko github page one evening this week, and since have been working on strategies and back testing them in the Gekko web UI.
There are many indicators available, and the language is JavaScript so creating an algorithm is quiet good fun. You can create moving average based strategies in just a few minutes with the examples provided.
Trading is possible via API access to most of the popular exchanges (Poloniex, Bitfinnex, Kraken etc)
A back tester is included, data should be loaded in via the import option included and is best left running on a server then locally I found.
Download and have a try: https://github.com/askmike/gekko