In no particular order, the seven aspects to consider are:

Trust

As with anything dealing with money, the issue of trust is paramount.  You’ve got to be able to know, with absolute certainty, that when you issue a buy or sell order, the platform you’re using is going to see that trade executed when you want it.  There’s more to it than that, however.  The company has to have a foundation of rock-solid ethical principles and be absolutely beyond reproach.

Customer Service

One way that trading platforms can help build that trust is by providing whatever level of handholding their customers require.  Obviously, this will vary from one person to the next, but the bottom line is, when you have a problem, you want to know that the people behind the trading platform you’ve selected is on the case.  That they’ll fix your problems, address your concerns, and get you back to trading quickly, so you don’t miss any opportunities.

Platform Flexibility

There’s another dimension of customer service that’s worth mentioning here, too.  The trading platform you settle on has to be well designed, and frankly, it just has to work.  That means, it needs to be intuitive and easy to understand, so you don’t have to call customer service in the first place.  If the company has done their work well, about the only times you’ll ever have to reach out to their support team is if there’s some kind of systemic failure or issue, and those should be few and far between.  When they occur, your ideal trading platform will have you back up and running in record time.

Width and Breadth of Services Offered

This includes access to the most markets and the most types of trades.  The last thing you want in a trading platform is one that will limit your access to markets because it’s simply not very mature or well-developed.

Platform Availability

Ten years ago, you’d have probably been building your trading empire on a laptop.  These days, however, your options are wide open.  Some days, maybe you’ll be at your desktop PC.  Other days, you’ll be on the road, and the laptop is the most appropriate tool.  Still others, you might be using your smartphone or tablet.  You need a platform that is supported on every device type made, because that’s where the current state of the technology is.  It’s a high speed, flexible world, and if your chosen platform isn’t up to the task, then you’re going to lose opportunities.

Costs

The platform has to have low fees, and no hidden costs.  The lower the better, because lower costs mean higher total returns for you if you have traded successfully, and anything you can do to increase your potential returns is a good thing.

Tools

You want information at your fingertips.  The more the better, preferably organized in a clear, logical, and concise manner.  There’s no such thing as too much information, but unless that information is well organized, it’s going to be hard to turn it into actionable intelligence.  The trading platform you choose needs to provide those tools to you.  It’s just that simple.