usb otg thermal printer interface to android tab with usb device I have printer with USB OTG capability which I want to use with my Android Tab (as USB device).

Is this possible -- and if so, will it work for all Android versions from 2.3 up? Is there any driver needed for this communication?
Did you try this App?  Supports Ethernet, USB or Serial (with serial-USB adapter). 
https://play.google.com/store/apps/details?id=qsrtech.posprintdriver

Also, try this app from Opera Mobile Store. If this app doesn't work with your printer, send printer profile to the app server. They might add support.
http://apps.opera.com/en_in/usb_printer_driver_21_developer_edition.html