Google is expanding its movie playlist, adding nearly 500 titles such as “Captain America” and “Hugo” to its list of rentals on Google Play and YouTube.

Malik Ducard, director of content partnerships for YouTube, said in a statement that the rentals will be available to fans in the United States and Canada. Many of the movies are available today, and more will be added in the coming months.

The expanded catalog is thanks to a partnership with Paramount Pictures. Google, which is attempting to take on mobile competitors such as Amazon and Apple, now has content-sharing deals with from five of the six major studios (they have no deal with 20th Century Fox) and with 10 independent studios.

Rentals for the new movies will be priced the same as most rentals on Google Play: $3.99 for new releases and $2.99 for most older movies, with a $1 premium if you want HD content. Most titles will be available for 48 hours per rental.

Google is said to be preparing its own tablet and tablet store, and Android chief Andy Rubin has said that the company intends to “double down” on tablets in 2012.

The company will have to aggressively build out its online media store to market a breakout product comparable to Amazon’s Kindle Fire or Apple’s iPad, which make it in­cred­ibly easy to purchase movies, music and television shows directly from the device.

Bloomberg reported Tuesday that Amazon has been testing a system that would let users make purchases through mobile applications— something Apple and Google already do. That would put the three companies in even tighter competition for consumer dollars and eyeballs. According to the report, in-app purchases generated $970 million in 2011 and could account for as much as $5.6 billion in revenue by 2015.

Related stories:

Is Google planning iPad competitors?

YouTube launches new editing tool

Apple TV offers hints at Jobs’s vision for our living rooms