Electronic Voting Machines in India can be used as standalone units for convenience and security (many remote areas might not have a reliable network connection). They all must be brought to the counting station, just like physical ballot boxes.
The machines are then counted one by one, and the votes are cross-checked with the voter count. What happens if one machine has 10,000 votes, but the area only has 5000? The results are available in a matter of hours.
Moving all the machines securely to the counting station is the most difficult task. To give people assurance that every step is being done correctly, the counting is also available online.
Delhi Electronic Voting Machines under paramilitary force’s eye – India-dna