If you download a free trial of a trading platform from any major brokerage firm, it will also include a simulator and hundreds of other trading tools, with thousands of indicators and strategies and systems that can be tested on the simulator.

If you "practice" hitting buttons at random, the results will also be random.

If you "practice" using ignorance, what do you expect the result will be?

Most beginners think "practice" makes perfect, but only "perfect practice" makes perfect.

The proper use of a simulator is to test a trade plan or system or strategy. "Practicing" hitting buttons at random is a waste of time. Practicing applying knowledge to some known principle might be productive. Proper practice can only come from proper learning and proper application.

Investopedia is a good place to define financial terms and learn and they also have a simulator for practice.

http://www.investopedia.com/simulator/

you can download stock wars on Iphone.

http://www.tradingsimulation.com/

http://simulator.investopedia.com/

www.marketwatch.com/game/

http://www.moneyworks4me.com/

http://www.investopedia.com/