The whole furore over \u201cdeal or no deal\u201d and Brexit might seem like something that the average Aussie expat doesn\u2019t have to worry about, but if you have money tied up in investments, it\u2019s time to think again. Online trading is a great tool for adjusting your investment portfolio to react to changing times, so it is no surprise that there are more Brits dipping their toes into the murky waters of stocks, bonds and Forex than ever before. If you are thinking of joining them, the first thing you will need to do is select from the array of investment apps that are out there. Here are some key points to keep in mind when you make your choice. Cross-platform functionality This is the mobile age, so being able to access your trading account from your Android device is, of course, important. But while that is a useful tool for checking your portfolio on the go and reacting to market changes, when you do your serious research and study the different charts and indicators, you will soon find that small screen is an annoyance. Cross-platform functionality that allows you to use either a smartphone or a PC is a must. Practice makes perfect Leaping headlong into the world of trading with only a vague notion of what you are doing is an effective way to lose everything. The best trading apps feature a practice or demo account that allows you to learn the ropes without risking any real money. Take your time, research different strategies and then try putting them into virtual action. When you feel confident that you understand what strategy is going to work best for you, that\u2019s the time to start trading for real. Understand the costs Every platform operates as a business, so it needs to make money. This might be in the form of commissions, charges per trade or a monthly fee. Working out which is the most cost-effective depends entirely on the frequency and size of trades you will be making. This is why it is so important to have a firm strategy in mind before you begin. That way, you can put your shortlisted apps side by side on a spreadsheet and work out the actual costs. Keep your options openThere are lots of facets to trading, and while you might start out thinking you just want to trade stocks and shares, there is every chance you will later wish to explore bonds, CFDs, cryptocurrency and so on. The last thing you need is to find yourself having to install a whole new app, so make sure versatility and diversity of trading options is near the top of your priority list.