Sri Lanka is definitely more developed than India or any other country in the South Asia area. Their income is more than India, for sure. In fact, the people of Sri Lanka make about twice as much as those in India and sometimes even more.
Sri Lanka's economy is much better too. Sri Lanka has a much higher literacy rate too. It is also accredited to Sri Lanka that their government is more transparent, or at least attempts to be more so, than India. Sri Lanka is working towards becoming developed and each and every day they are taking strides to be.