Utilize your financial knowledge, give your answer or opinion to the input question or subject . Answer format is not limited.

How can online trading platforms be trustworthly? 
In most countries trading platforms are legally required to be overseen by a regulator, in the US this is the SEC (Securities and Exchanges Commission). This regulatory oversight is required in order to operate (i.e. have clients) in that country and the company will lose the right to operate in that country if they do not comply with the regulations. If you believe that you have genuine cause to complain that a trading platform that you are using within your jurisdiction is behaving unfairly towards you you can report this to the regulator and they will investigate so long as you can provide them with some concrete evidence. Note that in many jurisdictions gambling websites are also regulated (they are in the UK for example) and so arguments about their fairness are specious. A big problem with a lot of these complaints is that people who lose money are very vocal about blaming everyone else, people who make money are very vocal about their own amazing skills... think about that!