I'm not sure what you are after but I have an H2. For around $200US its not a bad recorder as long as you don't try to use the external mic port. I don't think there anything entry level that can beat that price. And I guess technically its a four channel recorder, four if you record in surround mode. You don't have to reduce that to stereo, but you can do that internally if you wish. For lowpro you can't get much more discrete. Its not a bad recorder straight out of the box. But you get what you pay for and there are other, better recorders depending on your needs.
So what do mean by "Trying to find out the purpose?" About the only recorder it goes head to head with it is the Edirol R-09. No mystery there, just two different companies building similar recorders. They are competing for that slice of the market. The R-09 seems to be more respected but I think that is mainly by people who have dismissed the H2 unfairly. The H-4 is a somewhat different beast all together and has its own advantages and disadvantages.