The main difference is the maximum length of stay:
- the eVOA allows a maximum of 60 days (30 days plus one 30-day extension),
- while the C1 tourist visa can be extended up to a total of 180 days.
The eVOA is also only available to citizens of certain countries, whereas the C1 is open to all nationalities (subject to embassy rules).
For short stays of up to 30 days, the eVOA is usually the faster and cheaper option. If you're planning a longer stay or want to extend multiple times, the C1 is the better fit. See our VOA vs. C1 comparison for more detail.