I played both Mobile Legends and Heroes Arena and if you are looking for reviews for both games, you are consulting the right guy. Although both games come in same genre both have their edge to one another. So if you are looking for a reason why playing Heroes Arena over Mobile Legends or vice-versa, I will review both games on every aspect.
Content
Since Mobile Legends is older than Heroes Arena, it has larger content from 29 characters to 20 characters of Heroes Arena as of January 30, 2017. Mobile Legends has also different modes to enjoy. But considering the features such as runes, Heroes Arena has more interesting system that goes like League of Legends. There you can set up the stats you want to take in battle and not just from pre-made stat boost of Mobile Legends.
Downloads
Currently Mobile Legends already reached more than 50 million downloads from half a year release. Heroes Arena has 5 million download from a month release. The figures shows how MOBA successfully dominated the gaming scene in mobile platforms. This is another factor as more players in game, the easier you can find teammate or opponent in queuing. This is a big downside for most new MOBA in mobile as few players comes long wait in match making. In Heroes Arena when you reach diamond division, it is really a long wait before you can play because only few players reach this tier how much more for Master division.
Connection Issue
I would say that Heroes Arena has more stable latency with 55ms compare to Mobile Legends 60ms from both Asia server. This is a serious factor why there are several players from ML transfer to HA because of their disappointing lag issues that they are experiencing over a half year. I’m an active member of both games forum and I know how serious this connectivity problem from most players.