I am developing an Google maps android application in which I want to use database in cloud for saving usernames, passwords, GPS Locations etc. Can any option to achieve this with free of cost ? If there are any examples, posts, or tutorials?
Updated
Now there are a lot of cloud providers , providing solutions like MBaaS (Mobile Backend as a Service). Some only give access to cloud database, some will do the user management for you, some let you place code around cloud database and there are facilities of access control, push notifications, analytics, integrated image and file hosting etc.
Here are some providers which have a "free-tier" (may change in future):
Also, the host yourself solution:
old
Google App Engine has a DataStore : https://developers.google.com/appengine/
You can create a free account, and host a sophisticated web service. As long as your app doesn't generate really massive server transactions and data daily, its free. SQL storage is available too, but at a cost.
Helpful links:
Quick setup : http://code.google.com/p/appengine-rest-server/
Real android example : http://macgyverdev.blogspot.in/2012/01/create-spring-rest-service-for-google.html