the problem is that you will not find easily a source that will allow you to monitor the trades in realtime.
I already tried and the brokers won't give you access to that. You will also need to have a very fast internet connection, because if you have a bit of lag, the stock price will already have changed when you submit your order.
I think the only thing you can do, is to poll a page every second and extract the price from the HTML.
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What you could do is an app that monitors a stock price, then warns you when it drops / rises so you can buy or sell manually.
???
During years, I wrote robots and used them on several markets with different brokers (FXCM, BestCFD, IG Markets, etc.). My robots were able to pass orders with a reasonable delay (one second at worst). I had my own cluster of servers in a datacenter (to avoid a failure of hardware, internet connection or electric circuit) and I used softwares like MultiCharts, ProRealtime, MetaTrader or AmiBroker to create my robots. My method was all about statistics analysis and I was very successful. BUT according to one of my brokers, I was an exception. Most of his clients were losing money, and it was not uncommon to see people lose everything in a short span of time because of the leverage effect. In 2014, the AMF (the french market authority) published a
survey on the results of individual investors on CFD and Forex markets from 2009 to 2012: 89% lost their money, with an average loss of 10887 euros/investor.
You have to know that some brokers are pure swindlers. Some others have very unfair practices and play clearly against you. On Wikipedia, you can read this about one of my former brokers: "The following year, in February and March 2011, a number of class actions lawsuits were filed against FXCM, alleging fraud and racketeering from deceptive and unfair trade practices, and misleading shareholders during the 2010 IPO. [...] In August 2011, the NFA fined FXCM $2M for slippage malpractices." FXCM at this time was one of the biggest and well-known brokers. It had a good reputation.
So, unless you have a deep knowledge of how work the financial markets and how to trade on them, STAY AWAY FROM THEM!!! Or just buy and sell stocks as our grandfathers did, on the long term...
Personaly, I stopped all my financial activities in 2010 because they caused me too much stress, I had more and more difficulties to be profitable, and above all I wanted to spend my time with my new born boy.
