Trystack is a good platform only for testing purposes it is free to use and they are using KVM visualization on OpenStack Runs on X86 platform architecture . For example developer can test their application or Test code in different platform CentOS, Fedora, Ubuntu, OpenSUSE
Note “Instances aredeleted after 24 Hours therefore you cannot place your production code on free TryStack Service”
But created account on TryStack will not deleted therefore you can create new instance any time.
For Create Account you have to join their Facebook Group they will manually approve group join request for use TryStack Service (OpenStack) .
Check below link for more details About TryStack Service :–