I want to create mobile app which can provide customer login my app also logged in my magento site.
Is it possible? How can I do it?
You mean, once user logged in through App they will automatically be logged in the website also at the same time?
Once user create the account or logged in the app with the same credentials they should be able to log-in on website?
I think should be
"Once user create the account or logged in the app with the same credentials they should be able to log-in on website?"
Is it possible?
Yes, its possible use Magento's default APIs or create custom API to create an account and login which should store the customer data in same Magento which you are using for website.
For SOAP APIs you can have a look here.
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