The National, which is set to be published on Monday by Newsquest, will only be published for five days and will cost 50p a copy.
A price tag of 45p had been suggested to reflect the percentage of people who voted for the Yes camp in Scotland's independence referendum.
Walker told the crowd the support for independence had and would continue to change:
We are no longer the 45. We are the 50-plus, and we will become the 60 and the 70.
Walker will edit the pro-independence daily, and said the paper's publishers needed to be convinced there was sufficient demand for such a newspaper.
Tim Blott, the Herald & Times Group managing director, commented:
It is the first time in many years that a new daily newspaper has been launched in Scotland. The National is an exciting opportunity to meet the needs of a very politically-engaged section of the Scottish population.
We recognise that launching a newspaper in 2014 is to some extent counter-intuitive but we consistently argue for the power of great journalism and informed opinion.
Earlier this month polling conducted by YouGov showed that Scots may vote Yes to independence if there was another referendum.
When “don’t know” answers are excluded, 52 per cent of those polled would vote Yes and 48 per cent No. With don’t knows, the percentages change to 49 for Yes and 45 for No.