For running tests execute this command:
mvn clean test -Denv=dev -Dgroups=Full -DforkCount=0 -Dsystem.test.os=iOS
====================== Done: Maven project, log4j, velocity report (fail.html), dataProvider from json, Groups support, passing parameters through testNG.xml
Multithreading through testng.xml: <suite parallel="classes" thread-count="4" .../>
==== Console multithreading doesn't: //https://groups.google.com/forum/#!topic/testng-users/Hx9Zk0PAjl4 mvn clean test -DsuiteXmlFile=TestNGSuiteConfig.xml -Denv=dev -Dgroups=Full -DforkCount=0 -Dbrowser=CHROME -DthreadCount=2 -Dparallel="classes"
This works: mvn clean test -Denv=dev -Dgroups=Full -DforkCount=0 -Dbrowser=FIREFOX
===-Ddataproviderthreadcount="6"