NRIs can have a Non Resident External (NRE) and Non Resident Ordinary (NRO) account to manage their incomes earned abroad and in India. Both are rupee designated accounts.
NRE accounts a Indian rupee accounts that are freely repatriable to your foreign bank account at any time. The income is deemed to have been earned out of India. Interest earnings in NRE accounts are not taxable in India.
NRO accounts are Indian rupee accounts that function much like resident savings accounts. The income is deemed to have been earned from India. Interest earnings in NRO accounts are taxable in India. Repatriations upto USD 1 million (check this) per year are permitted from NRO accounts.
You can use money from both NRO or NRE accounts to invest with Scripbox. We have no preference. However, if you are a tax resident in India, we recommend you consult a tax accountant on re-designating your NRE and NRO accounts to resident Indian accounts.