Apps for Pitch Deck

What are some best apps that are very good for creating pitch decks very easily? On another hand, what are the best pitch deck templates for pre-seed and seed founders?

I was discussing with an investor this week and he asked "who created your pitch deck?". It's not that the pitch deck is poorly done though. I think from his words, he doesn't think it conforms well enough to the requirements for an early-stage startup. That's because he later asked if I've seen the templates made by YC, Sequoia and 500 Startups.