Are alternative, mostly Asian, Android Markets safe and fair? I'm getting mailing from various alternative Android markets, mostly from Asian regions (last one from Ndoo Networks), offering hosting of my free Android app.

Although broader reach for my app would be certainly better, I still have some questions:


Are these Markets safe? 
They are getting access to some my credentials, they can distribute something on behalf of my name, like virus, or spam, etc.
Would it be fair for Google to host apps there? 
I mean Amazon is ok, that's fair competition, but I'm afraid these "noname" alternative markets are somehow using unfair benefit of the work of other


Does anyone have any good or bad experience with these markets?
Are these Markets safe? They are getting access to some my
  credentials, they can distribute something on behalf of my name, like
  virus, or spam, etc.


If they ask for permission to distribute your apps, then they're probably the least to worry about; you can always verify that your apk is being distributed unmodified by verifying the apk's signature with your public key. You can also publish your public key (but keep your private key private) so that people downloading from these alternative markets can verify for themselves that the apk came from you unmodified.


  Would it be fair for Google to host apps there? I mean Amazon is ok,
  that's fair competition, but I'm afraid these "noname" alternative
  markets are somehow using unfair benefit of the work of other


It would be just as fair as Amazon; in fact, it would generally be considered unfair monopoly if Google started hunting down these alternative markets. In any case, the Play Market does not provide paid apps in China (and many other countries), so it does not hurt their revenue stream.