Ever wondered how Chinese manufacture their gadgets(phones, tabs, etc) well here is a small brief about it
Step 1) Warehouse :- There will me many types of warehouses depending upon the perfect environment required for the various components.
Step 2) Production labs :- There will be many production labs for the assembly of the various mobile phones parts… Mainly in this step they assemble the required parts and upload the firmware and other necessary things.
Step 3) Testing :- The gadget is powered on and tested… during the testing procedure if any of the gadget failed to pass the test, It will be sent back to the production labs for the rectification of problem.
Further passed gadgets are sent for further testing like survival on high temperature and low temperature , battery, etc.. and gadgets are randomly tested again.
Step 4) Production :- This step involves in the packing of the gadget
Step 5) marketing :- Final product are sent to customs for the marketing of the gadget.
You can also check this video for more information